The Biggest Emerging MLB Star at Every Position Entering 2018

A new Major League Baseball season is coming. If it's anything like every other season in MLB history, it's going to bring a new wave of star players with it.

We don't know who they are yet. But we can guess.

Our goal is to analyze the biggest emerging star at every key position (i.e., all positions except designated hitter) going into the 2018 season. For this, a few ground rules apply:

• No All-Stars: Because players who have been All-Stars are already stars.
• No Major Award Winners: That excludes Rookies of the Year, MVPs and Cy Young Award winners.
• Emphasis on "Emerging": We want to keep the focus on players whose major league careers are in their infancy, so we're drawing a line at 300 games played for position players and 75 appearances for pitchers.
• Nobody from Last Year's List: Because it's only fair to turn the spotlight on a fresh group of players.

Otherwise, the players who made the cut are simply the ones with the best combination of ability and untapped upside.

Catcher: Willson Contreras, Chicago Cubs

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Age: 25

MLB Experience: 193 G

Willson Contreras is a member of the rarest of breeds: catchers who can hit.

He isn't quite on the level of New York Yankees All-Star Gary Sanchez, who's a tad younger yet boasts 53 home runs and a .920 OPS (that's a 138 OPS+). But with an .851 OPS (120 OPS+) and 33 homers through two seasons, the Venezuela native comes closer than most to being Sanchez's equal.

And he's trending upward. Even despite a hamstring injury that rendered him a spectator for six weeks, Contreras finished his sophomore season in 2017 with a .993 OPS and 10 homers in 38 games following the All-Star break.

"I do remember a lot of people talking about that, just saying how I got hot in the second half because I made the right adjustments," Contreras said, per Gordon Wittenmyer of the Chicago Sun-Times. "But I was just focused on having a good at-bat and getting a good pitch to hit."

As he looks to keep the hits coming, the other big test Contreras must pass in 2018 is to become more consistent on defense. The tools are there, though. Baserunners who test his arm are asking for trouble. And according to Baseball Prospectus' metrics, he proved in 2016 that he has strong framing and blocking in him.

At the least, Contreras can make his first All-Star team this year. At best, he can emerge as the Chicago Cubs' latest MVP candidate.

First Base: Greg Bird, New York Yankees

Rich Schultz/Associated Press

Age: 25

MLB Experience: 94 G

First base is swimming with both veteran and youthful talent. Among the latter group, Joey Gallo and Matt Olson are two lethal sluggers who haven't yet had a Cody Bellinger-like closeup.

The floor, however, belongs to Greg Bird.

Unlike Gallo, Bird doesn't have a 40-homer season to his name. Unlike Olson, he's also yet to put up a 1.000 OPS or slam 20 homers in a 36-game span.

But as long as he can stay on the field in 2018, Bird has as much power potential as either one of them.

The New York Yankee has had little trouble coming by homers in the majors when he's been healthy. He slammed 11 in 46 games at the end of 2015 and 11 in 38 games (including the postseason) at the end of 2017. His swing is built for keeping the ball off the ground (28.4 GB%) and hitting it hard (40.6 hard%). He also has an extreme pull habit (44.8 pull%) that should agree with Yankee Stadium's short porch.

Bird also teased a dramatic improvement with his plate discipline last year. He chased only 20.4 percent of the pitches he saw outside the strike zone, which placed him just behind Mike Trout in 15th place. That helped up his walk rate to 11.2 percent and drop his strikeout rate to 24.7 percent.

Gallo and Olson are talented hitters whose results have probably peaked. Bird is a talented hitter whose best should come soon.

Second Base: Ozzie Albies, Atlanta Braves

Rich Schultz/Getty Images

Age: 21

MLB Experience: 57 G

Ozzie Albies is a relative newcomer to The Show, and he doesn't carry as much hype as Yoan Moncada over in the American League.

But if anyone missed what Albies did in his debut with the Atlanta Braves last season, they missed something special.

Albies took 244 trips to the plate and came out with a .286/.354/.456 slash line. That's an .810 OPS, which equates to a 112 OPS+. The list of guys who've done that at the age of 20 includes Carlos Correa, Bryce Harper, Mike Trout, Giancarlo Stanton, Alex Rodriguez and Ken Griffey Jr.

Sure, sure. Small sample size and everything. Yet, what's under the hood of Albies' breakout is just as impressive. He showed patience (8.6 BB%) and made frequent contact (14.8 K%). And while he doesn't loom large at just 5'9" and 160 pounds, he also showed a knack for hard contact (33.2 hard%).

And, no, the Curacao native isn't just a hitter.

He's also a runner, as his average sprint (28.9 feet per second) was faster than all but two second basemen. And a defender, as he put up above average metrics.

Because he used up his rookie eligibility last season, the only thing Albies can't do in 2018 is win the National League Rookie of the Year. Otherwise, he's capable of becoming an All-Star.

Third Base: Matt Chapman, Oakland Athletics

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Age: 24

MLB Experience: 84 G

Remember that list of historic 20-year-old hitters that Ozzie Albies was on? Also on that list was Rafael Devers of the Boston Red Sox, whose 2017 rookie season produced a 112 OPS+ and 10 homers.

But since Devers slumped through a good portion of his debut and also struggled on defense, let's put the spotlight on Matt Chapman.

As Devers bumbled around at the hot corner in 2017, Chapman provided a highlight-heavy opening statement that suggests he might soon become the best defensive third baseman in baseball.

"His defensive metrics, any one that you look at, is off the charts," Oakland A's manager Bob Melvin said in October, per Alex Simon of MLB.com.

This is especially true of defensive runs saved. Chapman needed only 727 innings to push his DRS to 19. The only other non-catcher to accumulate such a high DRS in under 730 innings was Andrelton Simmons in 2012.

Chapman's bat isn't as dazzling as his glove yet is not to be underestimated. He managed a 110 OPS+ as a rookie last year mainly by way of his power. He slugged 14 homers via a swing that put only 33.5 percent of his batted balls on the ground.

Now that Manny Machado is at shortstop and Evan Longoria is in the National League, Chapman has a clear path to a Gold Glove in 2018. If he also keeps the power coming, that's unlikely to be the only accolade he takes home.

Shortstop: Paul DeJong, St. Louis Cardinals

Jeff Roberson/Associated Press

Age: 24

MLB Experience: 108 G

Among those who could join MLB's raucous shortstop party in 2018 are Amed Rosario of the New York Mets and Orlando Arcia of the Milwaukee Brewers.

But rather than trust them to ride their gloves to stardom, it's safer to trust Paul DeJong to ride his bat to higher levels of stardom.

There wasn't any national fanfare when the St. Louis Cardinals promoted DeJong last May, but he stuck around and did well enough to finish second to Cody Bellinger in the NL Rookie of the Year voting.

He accomplished that on the strength of 25 homers and a 121 OPS+. Here's a complete list of rookie shortstops who have hit those two marks:

• Paul DeJong, 2017
• Corey Seager, 2016
• Trevor Story, 2016
• Nomar Garciaparra, 1997

There's an upside and a downside to the fact that DeJong's hitting style is most comparable to that of Trevor Story's. The upside is that his talents for keeping the ball off the ground (33.7 GB%) and using his pull side (46.9 Pull%) should keep the power coming. The downside is that his less-than-stellar plate discipline (4.7 BB%) will make slumps a fact of life.

Even still, DeJong's power will keep him relevant on offense. On defense, he's at least a passable everyday shortstop.

Left Field: Rhys Hoskins, Philadelphia Phillies

Rich Schultz/Getty Images

Age: 24

MLB Experience: 50 G

Andrew Benintendi is another up-and-coming Boston Red Sox who's worthy of a name-drop. He's an excellent pure hitter and a pretty good athlete to boot.

Trouble is, Benintendi may not have the power to push his offensive ceiling to a level worthy of the biggest bats left field has to offer. A guy who most certainly does is Rhys Hoskins.

He first opened eyes with a .943 OPS and 38 homers in the minors in 2016. He punished Triple-A pitchers in 2017 and did the same to major leaguers after the Philadelphia Phillies called him up in August, clubbing 18 homers and compiled a 1.014 OPS.

The latter figure comes out to a 165 OPS+. That's rarefied air for rookie hitters and downright stratospheric for first-year hitters.

At 6'4", 225 pounds, Hoskins has the size to carry on as an elite slugger. He also has the swing, as he produced top-shelf marks of a 31.0 GB%, 46.0 hard% and 49.2 pull% in 2017. And above all, he has the patience. The 17.5 BB% he posted in the majors last year was only the latest case of him drawing more walks in the face of tougher competition.

There won't be as much to see when Hoskins is on the bases or on defense. But with a bat like his, that won't hold back his All-Star potential.

Center Field: Byron Buxton, Minnesota Twins

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Age: 24

MLB Experience: 278 G

If I had to guess, I'd say this is at least the 4,567th time Byron Buxton has been referenced as a star in the making.

But this time, it's truer than it's ever been.

Buxton played his first full season with the Minnesota Twins in 2017 and made good on his old prospect hype in two respects: He was really fast and really good at catching fly balls.

He sprinted at an MLB-best 30.2 feet per second and used that speed to steal 29 bases in 30 tries. On defense, he led all center fielders with 24 defensive runs saved and all outfielders with 25 outs above average.

As Twins second baseman Brian Dozier said of Buxton's defense, according to Rhett Bollinger of MLB.com, "It bugs me that he's even compared to other guys because when you play with him, you see the balls he gets to nobody else can get to."

At the plate, there's good and bad news about the 94 OPS+ Buxton mustered last year. The bad is that anything under 100 is below average. The good, however, is twofold: It marked a career high for the 2012 No. 2 pick and would have been even higher if he'd started his season-ending hot streak sooner.

Even if Buxton's offense doesn't pick up where it left off, he's still good enough to qualify as one of baseball's best all-around outfielders. But if it does, Minnesota will have an MVP candidate on its hands.

Right Field: Mitch Haniger, Seattle Mariners

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Age: 27

MLB Experience: 130 G

Baseball's right field ranks feature Bryce Harper, Giancarlo Stanton, Aaron Judge and Mookie Betts at the top and then a steep drop-off to a gaggle of players with relatively limited upside.

But if there's a guy worth keeping an eye on, it's Mitch Haniger.

He took a slower route to the majors and thus isn't as experienced as a lot of guys his age. It also doesn't help that injuries sabotaged his first full season with the Seattle Mariners in 2017.

Nonetheless, Haniger played 96 games and finished with a 126 OPS+ and 16 homers. Those are the marks of an above-average hitter. And it's notable that Haniger looked like far more than above average when he was healthy at the beginning and end of the year:

• Through April 25: .342/.447/.608 with 4 HR in 21 G
• From Aug. 19: .318/.344/.580 with 9 HR in 38 G

Through it all, Haniger also played a good right field, tallying eight defensive runs saved and a 3.6 ultimate zone rating.

Since staying healthy is Haniger's biggest priority for 2018, it's not the best omen that he came down with a hand injury Saturday. But if he can get over that, he's a guy to watch as a sleeper All-Star candidate.

Starting Pitcher: Aaron Nola, Philadelphia Phillies

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Age: 24

MLB Experience: 60 G

There's a slew of young starters who could realize their All-Star potential in 2018. Shohei Ohtani is one. Jose Berrios and Luis Castillo are two more.

What separates Aaron Nola is just how close he is already.

Though his 3.94 career ERA doesn't jump off the page, Nola has done two things better than most young pitchers. One is strike hitters out, as he owns a career whiff rate of 9.4 batters per nine innings. Another is limit walks, as he's walked only 2.4 batters per nine innings.

The list of pitchers who've made at least 60 starts through their age-24 seasons while putting up numbers like those is not long:

• Aaron Nola
• Noah Syndergaard

At last check, Nola's results were starting to line up with his ability. He recorded a 3.54 ERA over 168 innings in 2017, benefiting from extra velocity on his fastball as well as continued nastiness from his curveball and changeup. As always, his command of all his pitches was impeccable.

The only thing Nola has to do now is stay healthy. If he can, he'll have cleared the last remaining barrier between him and a rise to All-Star status.

Relief Pitcher: Chad Green, New York Yankees

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Age: 26

MLB Experience: 52 G

Relief pitchers can fall just as quickly as they rise. Knowing that, perhaps Chad Green ought to be nervous as he prepares to enter his first full year in the New York Yankees bullpen.

Or he could trust that his four-seam fastball is going to be just as overpowering in 2018 as it was in 2017.

It's really all the right-hander needed to notch a 1.83 ERA and strike out batters at six times the rate he walked them last year. He threw it often, and it blew away a fairly notable reliever for the MLB lead in weighted on-base average (basically a more complex version of OPS) against a four-seamer:

• Vs. Chad Green's four-seamer: .169 wOBA
• Vs. Craig Kimbrel's four-seamer: .199 wOBA

It wasn't just Green's average velocity of 95.8 mph that made a difference. His four-seamer also had an elite spin rate, which made it difficult to pick up.

"It jumps on you. He's got such good spin rate and he gets behind the ball so well, I think that's what surprises hitters the most," fellow Yankees reliever David Robertson said in October, per Mark Feinsand of MLB.com.

So, don't just look at Robertson, Aroldis Chapman, Dellin Betances and Tommy Kahnle as potential All-Stars out of the Yankees pen. Green is right there, too.

Stats courtesy of Baseball Reference, FanGraphs and Baseball Savant.