Ranking MLB's 25 Best Under 25 Entering the 2016 Season

Joel Reuter@JoelReuterBRFeatured ColumnistJanuary 25, 2016

Ranking MLB's 25 Best Under 25 Entering the 2016 Season

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    Gene J. Puskar/Associated Press

    The MLB landscape has been flooded with young talent in recent years, and with no shortage of high-profile prospects on the horizon, that's a trend that doesn't figure to end anytime soon.

    Ahead, we've ranked the top 25 players in the league under the age of 25, with the cutoff being the player's age when Opening Day arrives April 3.

    A few more specifics before we begin:

    • MLB Experience Required: Only players with who have established themselves at the big league level were considered, so top prospects like Lucas Giolito, Julio Urias, J.P. Crawford, Trea Turner and Tyler Glasnow don't qualify just yet.
    • Rookie Eligibility Was a DQ: Players who have had a taste of the big leagues but still hold rookie eligibility were also excluded from consideration, like Corey Seager, Byron Buxton, Steven Matz and Jon Gray.
    • Production Over Upside: Eligible players were chosen based on their current skill level and past production, not on their overall ceiling and future upside.
    • Expect Things to Change: This list is a reflection of where the top under-25 talent in the league stands entering the 2016 season, but expect the list to look different by next offseason. For example, right now Manny Machado and Nolan Arenado have accomplished more than Kris Bryant, but it wouldn't be at all surprising to see Bryant pass both of them in these rankings in the upcoming year.

    Let's kick things off with a few honorable mentions.

Honorable Mentions

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    Pirates OF Gregory Polanco
    Pirates OF Gregory PolancoRick Osentoski-USA TODAY Sports

    Position Players

    • 3B Nick Castellanos, DET
    • LF Michael Conforto, NYM
    • CF Delino DeShields Jr., TEX
    • CF Randal Grichuk, STL
    • UT Kike Hernandez, LAD
    • SS Ketel Marte, SEA
    • 2B Rougned Odor, TEX
    • CF Joc Pederson, LAD
    • RF Gregory Polanco, PIT
    • OF Eddie Rosario, MIN
    • RF Jorge Soler, CHC
    • C Blake Swihart, BOS


    • SP Andrew Heaney, LAA
    • RP Keone Kela, TEX
    • SP Aaron Nola, PHI
    • SP Joe Ross, WAS
    • RP Aaron Sanchez, TOR
    • SP Julio Teheran, ATL
    • SP Taijuan Walker, SEA

25. LF Christian Yelich, Miami Marlins

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    Steve Mitchell-USA TODAY Sports

    Born: December 5, 1991 (24 years old)

    Player Overview

    The No. 25 spot in these rankings was a tough call between a pair of corner outfielders in Gregory Polanco and Christian Yelich.

    Polanco may have the higher ceiling going forward, but based on what they've accomplished to this point in their respective careers, Yelich had to be the choice.

    The 24-year-old hit .300 for the first time last season while also posting a career-best .782 OPS and remaining a solid on-base threat with a .366 on-base percentage that is right in line with his .365 career mark.

    What really sets Yelich apart, though, is his defense.

    A Gold Glove winner in 2014, he's posted 13 defensive runs saved in left field each of the past two seasons.

    The Miami Marlins locked him up with a seven-year, $49.57 million deal last offseason. He gives them another long-term piece of the puzzle alongside Giancarlo Stanton and recently extended Dee Gordon.

24. SP Yordano Ventura, Kansas City Royals

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    John Rieger-USA TODAY Sports

    Born: June 3, 1991 (24 years old)

    Player Overview

    Yordano Ventura did not have the 2015 season many envisioned as the Kansas City Royals asked him to step into the role of staff ace after James Shields departed in free agency.

    He finished the year at 13-8 with a 4.08 ERA in 163.1 innings, but the pieces started to fall into place down the stretch.

    His ERA climbed as high as 5.29 on Aug. 6, but he finally started to look like an ace after that as he closed out the year at 7-1 with a 2.38 ERA over his final 11 starts.

    Unfortunately, that strong finish did not carry over into October, as he went 0-2 with a 6.43 ERA in five postseason starts, but his strong finish to the regular season should still give him something to build on heading into 2016.

    Ian Kennedy has been added to the mix, according to MLB Network's Jon Heyman, and Chris Young was also re-signed, but Ventura will once again be asked to fill the role of staff ace.

    That five-year, $23 million extension he signed prior to last season, which includes a pair of option years at $12 million each, could still wind up being an absolute steal for the Royals.

23. SP Eduardo Rodriguez, Boston Red Sox

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    Dan Hamilton-USA TODAY Sports

    Born: April 7, 1993 (22 years old)

    Player Overview

    The Baltimore Orioles are going to get awfully tired of looking at Eduardo Rodriguez in a Boston Red Sox uniform before his career is over.

    Baltimore sent Rodriguez to Boston in exchange for reliever Andrew Miller at the trade deadline in 2014, and he quickly established himself as one of the game's most promising young starters last season.

    Rodriguez debuted with a bang on May 28, allowing just three hits and striking out seven in 7.2 scoreless innings against the Texas Rangers to earn the victory.

    He struggled at times with tipping his pitches and had four particularly rough starts in which he went 0-4 and allowed a combined 30 earned runs in 15 innings of work.

    However, he still finished the year at 10-6 with a 3.85 ERA, 1.290 WHIP and 98 strikeouts in 121.2 innings of work over 21 starts, and he often showed flashes of bigger and better things to come.

22. RP Roberto Osuna, Toronto Blue Jays

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    Tom Szczerbowski/Getty Images

    Born: February 7, 1995 (20 years old)

    Player Overview

    The youngest player on this list—and, in fact, the youngest player in the majors last season—Roberto Osuna proved to be an integral piece of the Toronto Blue Jays' run to the American League Championship Series.

    A starter during his rapid ascent through the minor league ranks, Osuna broke camp with a spot in the Blue Jays bullpen.

    After Brett Cecil and Miguel Castro both failed to lock down the closer job, Osuna took over ninth-inning duties with his first career save on June 22.

    From that point on, he converted 20 of 22 save chances with a 2.87 ERA, 0.903 WHIP and 9.6 K/9.

    The addition of Drew Storen this offseason could mean Osuna moves to a setup role, and his ability to go multiple innings could actually wind up being more valuable to the bullpen as a whole.

    At some point, the Blue Jays could opt to return Osuna to the starting rotation, but for now he's a key piece of the relief corps in whatever role he fills.

21. SP Carlos Rodon, Chicago White Sox

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    Born: December 10, 1992 (23 years old)

    Player Overview

    If there's one player from the bottom end of these rankings who has the best chance of climbing his way into the top 10 by next season, it might be Chicago White Sox starter Carlos Rodon.

    The consensus top player in the 2014 draft heading into his junior season at NC State, he instead slipped to No. 3 overall after dealing with some arm issues.

    The White Sox were more than happy to select him there, and while started the 2015 season in the minors, he wasn't down for long, as he joined the big league bullpen on April 21.

    After three relief appearances, he moved into the rotation and stuck there the rest of the year, going 9-6 with a 3.79 ERA, 1.414 WHIP and 135 strikeouts in 133 innings.

    The stuff is there for Rodon to be a legitimate second ace for the White Sox alongside Chris Sale, but his control is still the one major question mark.

    He finished the season with 71 walks in 139.1 total innings, which gave him a 4.59 BB/9.

    That was the worst walk rate among the 141 pitchers who threw at least 100 innings last season, and it will have to improve if he's going to realize his vast potential.

20. SP Lance McCullers, Houston Astros

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    Kevin Jairaj-USA TODAY Sports

    Born: October 2, 1993 (22 years old)

    Player Overview

    The Houston Astros selected Lance McCullers with the No. 41 pick in the same 2012 draft that saw them choose shortstop Carlos Correa with the first overall pick.

    It took an above-slot bonus of $2.5 million to sign him away from his commitment to the University of Florida, but that has already proved to be money well spent.

    After a rocky 2014 season saw him post a 5.47 ERA in 97 innings of work at the High-A level, his stock was down heading into last season, and Baseball America ranked him as the No. 11 prospect in a deep Astros system.

    He opened the 2015 season on fire in Double-A, though, posting a 0.56 ERA, 0.938 WHIP and 48 strikeouts in 32 innings of work, and got the call when an injury to Brett Oberholtzer opened up a spot in the Houston rotation.

    There were some ups and downs, but as a whole his rookie season proved to be a great one, as he went 6-7 with a 3.22 ERA, 1.186 WHIP and 129 strikeouts in 125.2 innings over 22 starts.

    He also took the ball in Game 4 of the ALDS, allowing two hits and two earned runs while striking out seven in 6.1 innings of work for a no-decision.

19. C/OF Kyle Schwarber, Chicago Cubs

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    Jerry Lai-USA TODAY Sports

    Born: March 5, 1993 (22 years old)

    Player Overview

    His long-term future behind the plate is still very much in question, but Kyle Schwarber can hit, that much is for sure.

    After going 8-for-22 with six RBI in a brief six-game promotion in June to serve as designated hitter during an AL road trip, Schwarber returned for good a month later to give the Chicago Cubs offense a shot in the arm.

    Despite a relatively low .246 batting average, Schwarber finished his rookie season with an .842 OPS thanks to his 16 home runs in just 232 at-bats.

    He followed that up with a huge postseason, as he went 9-for-27 with five home runs and eight RBI in nine games.

    His defense in left field is an adventure, and he didn't hit left-handed pitching at all last year with a .143 average and .481 OPS against southpaws.

    That said, he's still a safe bet for 30-plus home runs over a full season of at-bats, and his good plate discipline should help offset a potentially low batting average.

18. SP Luis Severino, New York Yankees

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    Born: February 20, 1994 (21 years old)

    Player Overview

    Luis Severino was one of the breakout prospects of 2014, as he climbed three levels to finish the year in Double-A and went a combined 6-5 with a 2.47 ERA, 1.062 WHIP and 127 strikeouts in 113 innings of work.

    He was back in Double-A to begin the 2015 season, and the New York Yankees held off promoting him as long as they could so as not to rush the young right-hander, but he finally debuted as a 21-year-old on Aug. 5.

    That was early enough for him to make 11 starts down the stretch, and he was arguably the team's best starter, going 5-3 with a 2.89 ERA, 1.203 WHIP and 56 strikeouts in 62.1 innings.

    Those numbers don't tell the story of just how good Severino was as a rookie, though, as a rough start Sept. 11 against the Toronto Blue Jays (2.1 IP, 6 H, 6 ER) inflated his final line. In his other 10 starts, he went 5-2 with a 2.10 ERA and 1.100 WHIP.

    A legitimate breakout season could be coming in 2016.

17. 3B Maikel Franco, Philadelphia Phillies

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    Bill Streicher-USA TODAY Sports

    Born: August 26, 1992 (23 years old)

    Player Overview

    The Philadelphia Phillies did not have many long-term building blocks when the 2015 season began, and Maikel Franco was among the biggest question marks.

    After a huge 2013 season between High-A and Double-A, Franco struggled at the Triple-A level in 2014 when he hit .257/.299/.428 with 16 home runs in 521 at-bats.

    He was back in Triple-A to start last season, but it didn't take long to see he had turned a corner, and after posting a .355/.384/.539 line over 33 games he was promoted May 15.

    A wrist injury suffered on a hit-by-pitch sidelined him on Aug. 11, and he would play just three more games the rest of the way, but he still finished with impressive overall numbers.

    In what amounted to 80 games and 304 at-bats in the majors, he hit .280/.343/.497 with 22 doubles, 14 home runs and 50 RBI.

    He'll be asked to anchor a young Phillies lineup in 2016 and moving forward, and he has the tools to hit for a solid average and be a perennial 30-homer threat in the process.

    The one big question mark is his defense at third base, as the defensive metrics (minus-8 DRS, minus-17.0 UZR/150) were not kind to him. Long-term, a move across the diamond to first base may prove to be a necessity, but his bat will play anywhere.

16. 3B/OF Miguel Sano, Minnesota Twins

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    Born: May 11, 1993 (22 years old)

    Player Overview

    Miguel Sano was on the cusp of reaching the big leagues heading into the 2014 season when Tommy John surgery effectively ended his season before it even started in March.

    That meant Minnesota Twins fans would have to wait an extra year for the slugger to arrive, and he proved to be worth the wait in 2015.

    Sano made his debut July 2 hitting in the No. 6 spot in the Twins lineup.

    By the end of the week he had been bumped up to the No. 5 spot, and on July 7 he moved into the cleanup spot, where he batted most of the rest of the season.

    Sano wrapped up the year hitting .269/.385/.530 with 17 doubles, 18 home runs and 52 RBI in 279 at-bats.

    His .916 OPS ranked 11th among players with at least 300 plate appearances, and he's legitimately capable of that level of production over a full season.

    He'll be learning a new position this year as he moves to the outfield, but regardless, he should once again be a force in the middle of a sneaky good Twins lineup.

15. SS Addison Russell, Chicago Cubs

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    Charles LeClaire-USA TODAY Sports

    Born: January 23, 1994 (22 years old)

    Player Overview

    With a hole to fill at second base, the Cubs threw Addison Russell into the fire April 21.

    The 21-year-old was playing in his sixth career game at second base when he made his big league debut, but he played Gold Glove-caliber defense at the new position (9 DRS, 13.6 UZR/150) while learning on the fly.

    Then he made the full-time move to shortstop, where he figures to be a staple for the next decade, and he graded out even better (10 DRS, 20.4 UZR/150) back at his natural position.

    Those 10 defensive runs saved look great on the surface, but they're even more impressive when you consider he spent just 471.1 total innings at shortstop.

    Then there's his offensive game, which quietly came together after the All-Star break when he posted a .744 OPS with 13 doubles and eight home runs.

    He's capable of even more than that offensively, and an improving bat coupled with his Gold Glove-caliber defense could make him a 5.0-6.0 WAR player in his sophomore campaign.

14. SP Noah Syndergaard, New York Mets

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    Anthony Gruppuso-USA TODAY Sports

    Born: August 29, 1992 (23 years old)

    Player Overview

    Matt Harvey and Jacob deGrom are both great pitchers, but don't be surprised if it's Noah Syndergaard who winds up being the best starter in a stacked New York Mets rotation.

    Thor is three years younger than Harvey and four years younger than deGrom, but he had already established himself as a front-line arm in his own right by the end of his rookie season.

    The big 6'6" right-hander is an imposing figure on the mound, and his power stuff makes him that much more intimidating.

    His 97.1 mph average fastball velocity was the highest among pitchers with at least 150 innings pitched, and he pairs it with a nasty curveball and a solid changeup.

    However, the most impressive part of his debut was his command, as he walked just 31 hitters for a 1.9 BB/9 walk rate. That's good for anyone, but especially for a young power pitcher.

    Syndergaard finished at 9-7 with a 3.24 ERA, 1.047 WHIP and 166 strikeouts in 150 innings, earning him a fourth-place finish in NL Rookie of the Year voting, and he's capable of so much more going forward.

13. RHP Marcus Stroman, Toronto Blue Jays

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    Tom Szczerbowski/Getty Images

    Born: May 1, 1991 (24 years old)

    Player Overview

    The 2015 season was supposed to be a lost year for Marcus Stroman after he suffered a torn ACL during spring training.

    Instead, he made an incredibly quick recovery and returned to go 4-0 with a 1.67 ERA and 0.963 WHIP in four starts down the stretch.

    That was enough to earn him the No. 2 spot in the Toronto Blue Jays playoff rotation, and he went 1-0 with a 4.19 ERA over three starts in his first taste of playoff baseball.

    Now that David Price has moved on and the team opted against breaking the bank on another front-line starter, it's Stroman who will be asked to step into the role of staff ace.

    Despite his undersized 5'8" frame, there is little question he's up to the task, as he has the electric stuff and bulldog mentality to match up with the game's best starters.

    Stroman was 11-6 with a 3.65 ERA, 1.171 WHIP and 111 strikeouts in 130.2 innings as a rookie in 2014.

12. SP Michael Wacha, St. Louis Cardinals

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    Charles LeClaire-USA TODAY Sports

    Born: July 1, 1991 (24 years old)

    Player Overview

    Michael Wacha became a household name during the 2013 postseason, as he allowed just one hit in 7.1 innings against the Pittsburgh Pirates in his lone NLDS start and then outdueled Clayton Kershaw twice with 13.2 scoreless innings in the NLCS to win MVP honors.

    Pegged by many as a breakout star heading into 2014, he was instead limited to just 19 starts and 107 innings while dealing with a stress fracture in his right shoulder that cost him nearly three months.

    Back healthy in 2015, he earned his first All-Star appearance and went 17-7 with a 3.38 ERA, 1.213 WHIP and 153 strikeouts in 181.1 innings of work.

    A healthy Adam Wainwright should give the St. Louis Cardinals rotation a boost in 2016, but the 34-year-old is coming down the homestretch of his impressive career.

    The Cardinals have a number of quality young arms in the organization, including the next guy on this list, but Wacha is the best bet to take over as staff ace once Wainwright retires.

11. SP Carlos Martinez, St. Louis Cardinals

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    Born: September 21, 1991 (24 years old)

    Player Overview

    Michael Wacha may be the safer bet to be the workhorse ace of the St. Louis Cardinals rotation long-term, but Carlos Martinez has an electric arm and the higher ceiling.

    Martinez also had the better all-around season in 2015, so that combination of potential and production earns him the higher spot in these rankings.

    Also an All-Star for the first time last year, Martinez went 14-7 with a 3.01 ERA, 1.286 WHIP and 184 strikeouts in 179.2 innings.

    That was good enough to rank inside the top 10 in the NL in wins (seventh), ERA (10th) and K/9 (10th). Not too shabby for his first full season as a starter.

    It wasn't all good for Martinez in 2015, though, as a shoulder strain forced him out of his start against the Milwaukee Brewers on Sept. 25 and wound up sidelining him for the playoffs.

    He's expected to be back at 100 percent for spring training, and the Cardinals will need another front-line performance out of him in 2016 if they hope to maintain NL Central supremacy.

10. SS Xander Bogaerts, Boston Red Sox

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    Kim Klement-USA TODAY Sports

    Born: October 1, 1992 (23 years old)

    Player Overview

    After a strong debut saw him push his way into the starting lineup during the postseason, Xander Bogaerts entered the 2014 season as the heavy favorite to win AL Rookie of the Year honors.

    Instead, his first full season proved to be something of a disappointment, as he hit .240/.297/.362 with 28 doubles, 12 home runs and 46 RBI and struggled at times defensively on his way to a 0.3 WAR.

    There's a reason he was such a highly regarded prospect coming through the Boston Red Sox system, though, and he took a huge step forward last season.

    He upped his batting line to .320/.355/.421, finishing second in the AL in batting average and raising his OPS by 116 points.

    Bogaerts was also second on the team in RBI (81) and runs scored (84) while spending the bulk of the year hitting in the No. 3 spot in the lineup.

    The one disappointment of sorts was his lack of power, as he hit just seven home runs in 613 at-bats, but that should also improve going forward.

9. SS Francisco Lindor, Cleveland Indians

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    Charles LeClaire-USA TODAY Sports

    Born: November 14, 1993 (22 years old)

    Player Overview

    Francisco Lindor already had a big league-ready glove at the shortstop position when the Cleveland Indians selected him with the No. 8 overall pick in the 2011 draft.

    The question was whether or not his bat would eventually catch up.

    Suffice it to say he answered that question this past season, as he hit .313/.353/.482 with 22 doubles, 12 home runs and 51 RBI in 390 at-bats to finish second in AL Rookie of the Year voting.

    Lindor hit .279/.354/.384 in parts of five minor league seasons, so his offensive outburst upon arriving in the majors was surprising, and some modest regression should be expected.

    That said, he's still more than capable of being a plus offensive option at a premium position, and his glove was as good as advertised.

    He finished with 10 DRS and an 18.9 UZR/150. While Andrelton Simmons' move to the American League will complicate things, Lindor has legitimate Gold Glove potential.

8. SP Jose Fernandez, Miami Marlins

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    Steve Mitchell-USA TODAY Sports

    Born: July 31, 1992 (23 years old)

    Player Overview

    Recovery from Tommy John surgery kept Jose Fernandez sidelined until July 2 last season, but he returned as the same dominant pitcher we saw before he went under the knife.

    All told, Fernandez has gone 22-9 with a 2.40 ERA, 1.014 WHIP and 336 strikeouts in 289 career innings, and he's just getting started as he enters his age-23 season.

    As good as those overall numbers are, he's been on a different level entirely when pitching at home.

    In 26 career starts at Marlins Park, Fernandez has gone 17-0 with a 1.40 ERA and 0.901 WHIP, giving the home crowd something to cheer about in what has been a trying few years for the Marlins.

    With Scott Boras as his agent, it remains to be seen if the Marlins will be able to hold on to Fernandez long-term, but for the time being he'll again front their rotation as one of the best starters in the National League.

    He was 6-1 with a 2.92 ERA in 11 starts last season, and he should be a legitimate NL Cy Young candidate another full offseason removed from surgery.

7. RF Mookie Betts, Boston Red Sox

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    Mark L. Baer-USA TODAY Sports

    Born: October 7, 1992 (23 years old)

    Player Overview

    Mookie Betts showed last year why he was such a highly regarded piece of the Boston Red Sox organization.

    In his first full season in the majors, Betts hit .291/.341/.479 with 42 doubles, 18 home runs, 77 RBI, 92 runs scored and 21 stolen bases.

    A second baseman during his time in the minors, he was also a stellar defender in center field with 9 DRS and a 1.8 UZR/150.

    All of that added up to a 6.0 WAR, good for seventh among AL position players.

    Betts will slide over to right field this coming season to make room for Jackie Bradley Jr., and while he's not the prototypical power bat at the position, his all-around offensive game should still make him one of the more productive right fielders in the game.

    Betts and the aforementioned Xander Bogaerts are set to take over as the faces of the franchise for the Red Sox, and the organization looks to be in good hands.

6. 3B Kris Bryant, Chicago Cubs

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    Jerry Lai-USA TODAY Sports

    Born: January 4, 1992 (24 years old)

    Player Overview

    Kris Bryant entered his rookie season with as much hype as any prospect in recent memory, and he did not disappoint.

    The Chicago Cubs third baseman won NL Rookie of the Year honors unanimously, hitting .275/.369/.488 with 31 doubles, 26 home runs and 99 RBI for a 5.9 WAR.

    Those numbers would have been even better if not for a miserable month of July when he hit just .168/.270/.368, but he showed resolve and bounced back to finish the year strong.

    Detractors will point to his NL-high 199 strikeouts, but they were accompanied by 77 walks, which ranked 10th in the league.

    That discipline is a good indicator that he has a plan at the plate and isn't just up there hacking, and he should make more consistent contact going forward.

    His offensive game is what gets fans excited, but he was also much better than expected defensively at third base (3 DRS, 5.4 UZR/150), and an eventual move to a corner outfield spot no longer looks like a necessity.

5. SS Carlos Correa, Houston Astros

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    Born: September 22, 1994 (21 years old)

    Player Overview

    Carlos Correa was the third-youngest player in the majors last season, but he looked like a seasoned veteran hitting in the No. 3 spot in the lineup for a contending Houston Astros team.

    He edged out Francisco Lindor for AL Rookie of the Year honors on the strength of a .279/.345/.512 line that included 22 doubles, 22 home runs and 68 RBI in 387 at-bats.

    Those 22 home runs at the shortstop position were a franchise record for the Astros, and he figures to up that mark at least a few times in the years to come.

    On top of his offensive game, which belies his age, Correa is a terrific defensive shortstop with an absolute cannon for an arm.

    An eventual move to third base is a possibility as his 6'4" frame continues to fill out and 2015 draft pick Alex Bregman potentially takes over at shortstop, but for now the Astros aren't sacrificing anything defensively having Correa man the shortstop position.

    Correa was a special player as a rookie, and he may only be scratching the surface.

4. 3B Nolan Arenado, Colorado Rockies

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    Charles LeClaire-USA TODAY Sports

    Born: April 16, 1991 (24 years old)

    Player Overview

    Already established as an elite defender after winning Gold Glove honors in each of his first two seasons in the league, Nolan Arenado took his offensive game up several notches last year.

    He hit .287/.323/.575 with 43 doubles, 42 home runs and 130 RBI, tying Washington Nationals outfielder Bryce Harper for the home run title and driving in 20 more runs than anyone else in the National League.

    Like most Rockies players, he did benefit from playing half his games at Coors Field, but he was still an elite-level producer on the road with an .835 OPS, 22 home runs and 56 RBI.

    Arenado also added a third Gold Glove award to his trophy case, and his 64 DRS over the past three seasons trails only Andrelton Simmons (94) and Jason Heyward (69) among all players.

    He'll turn 25 a couple of weeks into the 2016 season, so he'll be off this list shortly, but for now he remains one of the league's elite under-25 players.

3. 3B Manny Machado, Baltimore Orioles

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    Evan Habeeb-USA TODAY Sports

    Born: July 6, 1992 (23 years old)

    Player Overview

    After he suffered knee injuries in both 2013 and 2014, Manny Machado was finally healthy for an entire season last year, and a breakout offensive performance was the result.

    Machado hit .286/.359/.502 with 30 doubles, 35 home runs, 86 RBI and 20 stolen bases, shattering his previous career highs in both home runs (14) and steals (6) and helping offset the loss of Nelson Cruz in the Orioles lineup.

    He also improved his walk rate from 5.6 to 9.8 percent and cut his strikeout rate from 19.2 to 15.6 percent, which no doubt played a significant role in his offensive explosion.

    Meanwhile, he remained an elite defensive third baseman, winning his second Gold Glove award with 14 DRS and an 8.4 UZR/150.

    Machado debuted shortly after his 20th birthday back in 2012, and it's easy to forget he's still so young, as he was actually born six months after Kris Bryant.

2. RF Bryce Harper, Washington Nationals

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    Brad Mills-USA TODAY Sports

    Born: October 16, 1992 (23 years old)

    Player Overview

    After years of being consistently called the most overrated player in the game, Bryce Harper finally lived up to his billing as a future superstar with a monster 2015 performance.

    Harper hit .330/.460/.649 to lead the league in on-base percentage and slugging while also pacing the NL in home runs (42), runs scored (118) and WAR (9.9) on his way to unanimous MVP honors.

    His 195 OPS+ was the best since Barry Bonds in 2004 and ranks as the 71st-best single-season mark in baseball history.

    And all of that came before his 23rd birthday, as he'll play the entire 2016 season at the age of 23.

    A sharp spike in his walk rate from 9.6 to 19.0 percent was the biggest difference for Harper, and when pitchers did make a mistake over the plate, more times than not he crushed it.

    Harper was the best under-25 player in the league in 2015—and that may very well be the case again this coming year.

1. CF Mike Trout, Los Angeles Angels

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    Ed Szczepanski-USA TODAY Sports

    Born: August 7, 1991 (24 years old)

    Player Overview

    The gap between Mike Trout and Bryce Harper for the No. 1 spot in these rankings narrowed considerably this past season, but for the time being Trout maintains the top spot.

    The transition from power-speed threat to middle-of-the-order slugger continued for Trout this past season, as he hit a career-high 41 home runs and led the AL with a .590 slugging percentage and .991 OPS.

    In the process, he managed to trim his strikeout rate from 26.1 to 23.2 percent while raising his walk rate from 11.8 to 13.5 percent as he continues to tweak his approach.

    Another second-place finish in AL MVP voting makes it three times he's finished as the runner-up, to go along with winning the award in 2014, and there's no reason to think he won't again be among the leading candidates.

    Since his first full season in 2012, Trout has piled up a ridiculous 37.3 WAR.

    No one else is even over 30.0 during that span, as Pittsburgh Pirates center fielder Andrew McCutchen is second with a 26.3 WAR.

    All standard statistics and WAR totals courtesy of Baseball-Reference.com, while defensive metrics and pitch-velocity numbers come via FanGraphs.