Buying or Selling MLB's Biggest Early-Season Breakout Stars Entering May

Joel Reuter@JoelReuterBRFeatured ColumnistMay 1, 2019

Buying or Selling MLB's Biggest Early-Season Breakout Stars Entering May

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    Jonathan Daniel/Getty Images

    The start of a new MLB season always brings a handful of surprising breakout performances.

    For some players, it's the start of something big, the first step toward emerging as a superstar.

    For others, it's smoke and mirrors, aided by the deceiving combination of a small sample size and a run of good luck.

    Into which category do the early breakout stars of 2019 fall?

    Ahead we've taken a closer look at 10 notable early-season standouts, focusing on established players who are vastly exceeding their previous performances and rookies who have taken the league by storm.

    Each breakout star was given a buy or sell verdict to their March-April performances.

1B Pete Alonso, New York Mets

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    Michael B. Thomas/Getty Images

    Stats: 118 PA, .304/.398/.667, 18 XBH (9 HR), 25 RBI, 20 R

    Advanced: .367 BABIP, 11.9 BB%, 28.0 K%, 18.8 Soft%, 46.4 Hard%

    Pete Alonso gave us plenty of warning that a breakout season was coming.

    He hit .285/.395/.579 with 31 doubles, 36 home runs and 119 RBI in 132 games between Double-A and Triple-A last year and then posted an .849 OPS with seven doubles, six home runs and 27 RBI in 27 games in the Arizona Fall League.

    When the snow melted and spring training arrived, he picked up right where he left off, hitting .352/.387/.620 with 10 extra-base hits in 75 plate appearances to play his way onto the Opening Day roster.

    So really, his performance so far as a rookie has been par for the course.

    Like most players with a BABIP north of .350 in the early going, he's likely due for a bit of regression in the batting average department.

    Still, there's no reason to think he can't finish his rookie season with something like a .270 average and .375 on-base percentage to go with 30-plus home runs and 100-plus RBI.

    He checks all the boxes to be a middle-of-the-order run producer for the next decade.

    Verdict: Buy

SS Tim Anderson, Chicago White Sox

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    Jonathan Daniel/Getty Images

    Stats: 99 PA, .375/.394/.615, 11 XBH (6 HR), 18 RBI, 21 R

    Advanced: .435 BABIP, 2.0 BB%, 21.2 K%, 16.0 Soft%, 29.3 Hard%

    Tim Anderson has brought some welcome swagger to the rebuilding Chicago White Sox this season. The 25-year-old enjoyed the first 20-20 season of his career last year with 20 home runs and 26 steals, both of which represented career highs.

    However, he hit just .240/.281/.406 for an 87 OPS+ in the process.

    This season, he's been hitting everything in sight. His .375 batting average leads the American League, and he's already tallied six home runs to go with an MLB-leading 10 steals.

    But it looks like a mirage.

    His .435 BABIP is the highest mark of any qualified hitter, and he's done it without making particularly good contact. His 29.3 percent hard-contact rate is 168th out of 191 qualified hitters and actually represents a slight decline from the 30.3 percent rate he posted in 2018.

    Meanwhile, a player who entered the season with a minuscule 3.4 percent walk rate has somehow found a way to walk even less, drawing just two free passes in 99 plate appearances. Once his luck evens out and his batting average regresses, he'll have nothing to fall back on.

    Another 20-20 season with a sub-.300 on-base percentage seems like a reasonable expectation.

    Verdict: Sell

SP Luis Castillo, Cincinnati Reds

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    Jamie Sabau/Getty Images

    Stats: 6 GS, 3-1, 1.23 ERA, 0.95 WHIP, 14 BB, 43 K, 36.2 IP

    Advanced: 2.52 FIP, 3.60 SIERA, .241 BABIP, 9.7 BB%, 29.9 K%

    A quick glance at the numbers Luis Castillo posted last season provided little reason to believe a breakout season was imminent.

    In his first full year in MLB, he finished 10-12 with a 4.30 ERA, 1.22 WHIP and 165 strikeouts in 169.2 innings over 31 starts. Solid numbers, but nothing that screamed "budding ace."

    Anyone who watched him pitch down the stretch last season, though, saw this coming from a mile away.

    After entering the final month of the season with a 5.07 ERA, Castillo caught fire in September, posting a 1.09 ERA, 0.85 WHIP and 34 strikeouts in 33 innings while holding opposing hitters to a .172 batting average.

    The biggest concern this year is a walk rate that is pushing 10 percent. Among 97 qualified starters, his 9.7 percent mark ranks 74th.

    It's not impossible to succeed with a walk rate that high, but it will put more pressure on him to limit hits. That's something he's done fantastically so far, with a .168 opponents' batting average and a reasonable .241 BABIP.

    A sub-3.00 ERA and 200 strikeouts are well within reach.

    Verdict: Buy

3B Hunter Dozier, Kansas City Royals

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    Jim McIsaac/Getty Images

    Stats: 103 PA, .349/.447/.686, 13 XBH (7 HR), 17 RBI, 14 R

    Advanced: .371 BABIP, 14.6 BB%, 17.5 K%, 10.1 Soft%, 46.4 Hard%

    Hunter Dozier finally received his first extended MLB look last season, and the results were less than encouraging.

    In 388 plate appearances, he hit .229/.278/.395 with 11 home runs and 34 RBI while also turning in below-average defensive metrics (-6 DRS, -12.5 UZR/150) at third base.

    The 2013 No. 8 overall pick has looked like an entirely different player this season. The stark improvements in his strikeout and walk rates speak to a new and improved hitter:

    • 2018: 28.1 K%, 6.2 BB%
    • 2019: 17.5 K%, 14.6 BB%

    The 27-year-old has also trimmed his soft-contact rate from 15.0 to 10.1 percent, and Statcast numbers from Baseball Savant show increases in exit velocity (89.5 mph to 93.6) and launch angle (13.1 degrees to 16.8).

    That .371 BABIP is going to level off, but the increase in power looks legitimate, and luck has nothing to do with his results at the plate—it's his overhauled approach.

    It took longer than expected for Dozier to carve out a role in the majors, but he's proving to be worth the wait.

    Verdict: Buy

SP Domingo German, New York Yankees

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    Sean M. Haffey/Getty Images

    Stats: 6 G, 5 GS, 5-1, 2.56 ERA, 0.85 WHIP, 9 BB, 32 K, 31.2 IP

    Advanced: 2.78 FIP, 3.86 SIERA, .198 BABIP, 7.3 BB%, 25.8 K%

    While injuries opened the door for Domingo German to pitch 85.2 MLB innings last season, the results were less than encouraging. In 14 starts and seven relief appearances, he posted a 5.57 ERA and 1.33 WHIP, allowing 8.5 hits per nine innings and a .242 opponents' batting average.

    So what has changed?

    The most obvious difference has been a vastly improved changeup, which has emerged as a reliable third offering alongside his mid-90s fastball and plus curveball, via Brooks Baseball:

    • 2018: 17.0% Usage, .333 BAA, .233 ISO
    • 2019: 17.6% Usage, .105 BAA, .105 ISO

    The importance of having a third viable pitch when working as a starter can't be overstated.

    Still, there's some clear regression coming for a pitcher who has the third-lowest BABIP (.198) among qualified pitchers.

    German might not be the next Yankees ace, but he has shown enough improvement to be capable of holding down a spot in the middle of the rotation.

    Verdict: Sell

SP Tyler Glasnow, Tampa Bay Rays

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    Mike Carlson/Getty Images

    Stats: 6 GS, 5-0, 1.75 ERA, 0.94 WHIP, 7 BB, 38 K, 36.0 IP

    Advanced: 2.68 FIP, 3.33 SIERA, .270 BABIP, 5.1 BB%, 27.7 K%

    For years, the book on Tyler Glasnow was that he had ace-caliber upside if he could find a way to improve his command.

    It appears he's found a way.

    In three seasons with the Pittsburgh Pirates prior to joining the Tampa Bay Rays last summer in the Chris Archer deal, Glasnow posted a 5.79 ERA while walking 5.8 batters per nine innings in 141.1 frames. Keeping his 6'8" frame in rhythm proved difficult, and his electric swing-and-miss stuff was undermined by an inability to locate his fastball.

    He looked like a different pitcher following the trade, posting a 4.20 ERA and a much more palatable 3.1 walks per nine innings in 11 starts.

    "Ever since we acquired [Glasnow], you've seen continual progress. Even last year, we saw a lot of progress, and this year, he's just taken off," manager Kevin Cash told Joon Lee of on Sunday. "He's pretty special when he's out on the mound. Really good hitters have difficult at-bats against him."

    The fact that he's allowed just seven walks in 36 innings this season is the culmination of everything he's been working on the past several years. His stellar early numbers are also accompanied by a rather high .270 BABIP—as good an indication as any that he's for real.

    Verdict: Buy

SP Chris Paddack, San Diego Padres

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    Denis Poroy/Getty Images

    Stats: 5 GS, 1-1, 1.67 ERA, 0.67 WHIP, 8 BB, 30 K, 27.0 IP

    Advanced: 2.86 FIP, 3.53 SIERA, .138 BABIP, 8.1 BB%, 30.3 K%

    When spring training began, no one expected Chris Paddack to break camp with a spot in the San Diego Padres rotation. After all, he had just 37.2 innings of experience above the High-A level and had never thrown 100 frames in a pro season, working a career-high 90.0 in 2018 in his return from Tommy John surgery.

    The 23-year-old forced the team's hand with a stellar showing, though, and he's looked right at home with a team on the rise.

    So what's to be made of his brilliant start?

    The thing that jumps out is his .138 BABIP. That's the lowest mark of any pitcher with at least 20 innings, and it's by an overwhelming margin:

    1. Chris Paddack, .138
    2. Yonny Chirinos, .182
    3. Matt Shoemaker, .183

    That figure could climb by more than 100 points and still be one of the lowest in baseball. It will be up to Paddack to prove he's capable of maintaining success when he pitches with more baserunners.

    Paddack has all the makings of a future ace. But he's been the luckiest pitcher in baseball, and it's hard to buy in to his breakout performance.

    Verdict: Sell...for now

SP Caleb Smith, Miami Marlins

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    Michael Reaves/Getty Images

    Stats: 5 GS, 2-0, 2.17 ERA, 0.83 WHIP, 7 BB, 37 K, 29.0 IP

    Advanced: 2.64 FIP, 3.00 SIERA, .226 BABIP, 6.4 BB%, 33.9 K%

    If unheralded left-hander Caleb Smith is still available in your fantasy league, add him immediately.

    The 27-year-old showed some strikeout potential last season when he fanned 88 batters in 77.1 innings while posting a respectable 4.19 ERA and 1.24 WHIP in 16 starts.

    His season was cut short by a lat injury that required surgery, however, and his potential went largely unnoticed since he was pitching for the also-ran Miami Marlins.

    Healthy once again this year, he's showing even better swing-and-miss stuff, raising his strikeout rate from 27.0 to 33.9 percent and lowering his walk rate from 10.1 to 6.4 percent.

    Maintaining that ultralow .226 BABIP will be tough, but the rest of his peripherals are strong enough to think his emergence as the ace of the rebuilding Marlins is legit.

    Verdict: Buy

SS Fernando Tatis Jr., San Diego Padres

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    Denis Poroy/Getty Images

    Stats: 111 PA, .300/.360/.550, 12 XBH (6 HR), 13 RBI, 14 R

    Advanced: .381 BABIP, 7.2 BB%, 28.8 K%, 24.6 Soft%, 43.5 Hard%

    Chris Paddack was not the only young Padres player who earned his spot on the Opening Day roster with a strong spring training.

    Twenty-year-old shortstop Fernando Tatis Jr. made his MLB debut on Opening Day after hitting .286/.355/.507 with 22 doubles, 16 home runs and 16 steals in 88 games at Double-A last year.

    So far, he's made a seamless transition to the big leagues.

    His .381 BABIP is going to regress, but his 7.2 percent walk rate and sub-30.0 percent strikeout rate are excellent signs, especially considering the Padres had been using him in the leadoff spot before a hamstring injury forced him to the injured list Tuesday.

    On top of his offensive numbers, he's also been a standout defender, tallying four defensive runs saved while making several highlight-reel plays.

    Even if he has some cold stretches at the plate, he's a good enough two-way player to still provide positive value. This is what a future superstar looks like.

    Verdict: Buy

1B Christian Walker, Arizona Diamondbacks

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    Matt York/Associated Press

    Stats: 109 PA, .316/.385/.633, 17 XBH (7 HR), 15 RBI, 16 R

    Advanced: .400 BABIP, 10.1 BB%, 28.4 K%, 7.5 Soft%, 68.7 Hard%

    Entering the 2019 season, Christian Walker had yet to find MLB success and had finished with a disappointing .163/.226/.388 line in 53 plate appearances last year.

    At the same time, he had little left to prove in the minors after posting a .922 OPS with 47 extra-base hits in 359 plate appearances at Triple-A Reno—his second consecutive strong showing at that level.

    At 28 years old, he was in danger of being slapped with the dreaded "Quad-A" label.

    But then the Arizona Diamondbacks traded Paul Goldschmidt, and a path opened for regular playing time at first base—an opportunity Walker has seized.

    While his unsustainably high .400 BABIP means a dip in batting average is inevitable, the quality of contact he's making provides plenty of reason for optimism.

    His 68.7 percent hard-contact rate is the highest in baseball among 191 qualifiers, while his 7.5 percent soft-contact rate is fourth-lowest among that group.

    Hit the ball hard, and good things will happen.

    Verdict: Buy


    All stats courtesy of Baseball Reference and FanGraphs unless otherwise noted and accurate through Monday.


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