The One Flaw Each Young MLB Star Must Improve in 2020
Even the best young players in Major League Baseball aren't perfect.
Well, maybe two of them are. There's Cody Bellinger, who co-led the majors in WAR and won the National League MVP Award as a 23-year-old in 2019. There's also the 22-year-old Yordan Alvarez, who established himself as an elite hitter en route to winning the American League Rookie of the Year Award last season.
Otherwise, we thought we'd pinpoint some easily pinpointable flaws that 12 young stars will have to address if (or when) play resumes in 2020.
Apart from requiring that they be 24 or younger for the coming season, we basically cherry-picked the players for this list. And while all of them are being held back in some way or another, some of their flaws are more glaring than others.
Let's begin with three pitchers and then examine nine hitters.
Chris Paddack, San Diego Padres: Develop a Usable Curveball
Despite a brief demotion and some tough tests in the middle of the season, Chris Paddack's rookie campaign with the San Diego Padres in 2019 yielded a 3.33 ERA over 140.2 innings.
The 24-year-old right-hander also put up some solid peripherals, including a 4.9 strikeout-to-walk ratio. Yet he likewise served up 23 home runs, and his swing-and-miss rate was only in the 46th percentile.
There's nothing wrong with Paddack's fastball, which sits in the mid-90s, or his changeup, which is a beauty. But those two pitches were basically all he had as a rookie.
He used his curveball only 10.4 percent of the time, and it got hit for a .267 average and .444 slugging percentage. Unsurprisingly, it was nothing special in terms of velocity (76.1 mph) or spin rate (10th percentile).
To his credit, Paddack made honing his curveball a point of emphasis during spring training. If he can turn it into a workable third pitch, he will at least have something else to show hitters to keep them from sitting on his two moneymakers.
Mike Soroka, Atlanta Braves: Throw More Changeups
In the process of putting up a 2.68 ERA over 174.2 innings in just his age-21 season, Mike Soroka was a trend-bucker for the Atlanta Braves in 2019.
How Soroka functions is kind of a long story, but the short version is that he has very good command of four pitches that allow him to show hitters a variety of speeds and movements. Of the bunch, his sinker and his slider were his favorites in 2019.
His most lethal pitch, however, was his changeup. Its 39.1 whiff percentage was the best of his four offerings. The same is true of its .247 xwOBA (xwOBA measures expected production based on the quantity and quality of contact against pitches).
Nevertheless, Soroka used his changeup only 12.4 percent of the time. He might at least experiment with using it more often in 2020—and perhaps stick with it if the early results prove encouraging.
Jack Flaherty, St. Louis Cardinals: Find a Third Pitch
It's hard to get any hotter than Jack Flaherty was in the latter half of 2019.
That was more or less the story of Flaherty's season, in which he threw only 12 percent curveballs and 2 percent changeups. Those figures might herald a bad platoon split, but he nearly matched his .566 OPS against right-handed batters with a .616 OPS opposite left-handed batters.
As such, the St. Louis Cardinals ace frankly doesn't need to change anything. And yet one can't help but imagine how much more dangerous he could become if he can develop another dependable secondary offering to go with his slider.
His curveball is a prime candidate for the job, as it boasts good speed (78.2 mph) with above-average vertical and horizontal movement. Fully unlocking that pitch may be his key to capturing a Cy Young Award in the very near future.
Vladimir Guerrero Jr., Toronto Blue Jays: Expand Strike Zone Coverage
To be fair, calling Vladimir Guerrero Jr. a "star" right now is a bit of a stretch.
He didn't quite live up to expectations as a rookie for the Toronto Blue Jays in 2019. In 123 games, he mustered a good-but-not-great .772 OPS at the plate and struggled defensively at third base.
Nevertheless, this is still a 21-year-old son of a Hall of Famer who torched the minor leagues to the tune of a .331/.414/.531 slash line. And his first major league season wasn't without signs of promise. Specifically, Guerrero had a 39-game stretch toward the end of 2019 in which he hit .350 with a 1.013 OPS.
Guerrero's best chance of harnessing that excellence lies in expanding his strike zone coverage. He barely got any hits up in the zone last year. He also swung through a bunch of pitches on the outside corner, the bulk of which were sliders.
Issues such as these aren't unexpected for a young player with limited major league experience. Guerrero's failing to conquer them would be more disappointing than his having them in the first place.
Keston Hiura, Milwaukee Brewers: Cut Down on Whiffs
If there was an underrated rookie season in 2019, it surely belonged to Keston Hiura.
He was only 22 when he debuted for the Milwaukee Brewers in May, and he played just 84 games, but he produced a .938 OPS and 19 home runs. To boot, his contact quality metrics (e.g., his exit velocity and hard-hit and barrel rates) all placed in at least the 90th percentile.
On a less bright side, Hiura also struck out 107 times in 348 plate appearances with a whiff rate that was in the third percentile. Such numbers point to major holes in his swing that pitchers may be better able to exploit in future seasons.
One thing Hiura could do is simply improve his chase rate after swinging at 31.8 percent of the pitches he saw outside the strike zone in 2019. But he also has issues inside the zone, specifically with fastballs in the top half of it.
In light of how pitchers have embraced the high fastball as a means to combat the launch angle revolution, Hiura should prioritize the latter issue. If he does, his own revolution might continue unabated.
Eloy Jimenez, Chicago White Sox: Lay Off the Junk
Though it took a while for Eloy Jimenez to really get going as a rookie in 2019, he eventually settled in for the Chicago White Sox and teased a future as an elite slugger.
Results-wise, there's plenty to like about the .828 OPS and 31 homers that he authored last year. The 23-year-old also put up some impressive batted ball numbers, including a hard-hit rate that placed in the 92nd percentile.
All Jimenez has to do now is make contact more often. He struck out in 26.6 percent of his plate appearances as a rookie with a whiff rate in the seventh percentile.
The bulk of Jimenez's swings and misses were against breaking and off-speed pitches, specifically on and around the outside corner of the zone. That had much to do with how he simply had a hard time laying off those pitches.
If he can so much as tone down his aggressiveness against low-and-away junk, he stands to draw more walks and could force pitchers to challenge him more often.
Ozzie Albies, Atlanta Braves: Improve from the Left Side
Though he's only 23, Ozzie Albies has already established himself as an All-Star second baseman who's still getting better.
He's produced 11 WAR in only 375 games for the Braves with a high-water mark of 5.2 just last season. He hit well with a .295 average and .852 OPS plus power (24 homers), speed (15 stolen bases) and generally well-rated defense.
However, Albies is also a switch-hitter with imbalanced production. Against lefties, he owns a .982 OPS. Against righties, his OPS is a significantly lower .744.
It's a good thing Albies draws more walks when batting from the left side, but that comes paired with more strikeouts and less frequent (see here and here) hard contact. Most of his swings and misses as a lefty come on the outside part of the zone, whereas few of his hits come up in the zone.
If Albies can address either or both of those issues, he stands to become an even more well-rounded star.
Gleyber Torres, New York Yankees: Tighten Up Approach
For one thing, Gleyber Torres should pick on opponents his own size when play resumes in 2020.
But as far as the New York Yankees might be concerned, there's much to be gained if Torres finds a more balanced approach at the plate. The 23-year-old's .338 career on-base percentage isn't bad, but it's not quite befitting of a player with such enormous potential.
Torres was one of the more aggressive swingers in the American League last season, in part because he wasn't shy about expanding the zone. Though he doesn't need to go from that to, say, copying Joey Votto's laser-eyed approach, it wouldn't hurt if he toned it down a little.
Strictly within the strike zone, Torres hasn't collected many hits in the upper third. Any improvements with that or his discipline issues could push him to new heights in his third season.
Fernando Tatis Jr., San Diego Padres: Cut Down on Whiffs
In 2019, Fernando Tatis Jr. debuted with a .969 OPS, 22 homers and 16 steals. The 21-year-old also amassed 4.1 WAR, which tied for second among rookie hitters.
He did all that in only 84 games—and as a clearly unfinished product.
The Padres would surely love it if Tatis played better defensively after posting below-average metrics last season. They would probably love it even more if he achieved greater consistency at the plate, where he must emphasize cutting down last year's 29.6 strikeout percentage.
One silver lining is that Tatis' zone discipline doesn't actually need much in the way of improvement. He just needs to be better at hitting what he swings at, as a 67.1 contact percentage isn't going to cut it.
In particular, Tatis must conquer fastballs in the top half of the zone and sliders on and around the outside corner. These aren't unusual missions for a young hitter, so one as obviously talented as Tatis should be capable of handling them.
Rafael Devers, Boston Red Sox: Catch Up Against Left-Handers
For Boston Red Sox third baseman Rafael Devers, last season was an exercise in realizing his potential.
After struggling in 2018, the 23-year-old broke out by hitting .311 with a .916 OPS and an MLB-high 359 total bases. This was despite an extraordinarily aggressive approach, which is a credit to both the quantity (only 119 strikeouts) and quality of his contact.
The lefty-swinging Devers did, however, maintain a sizable platoon split:
- vs. RHP: .996 OPS, 25 HR
- vs. LHP: .744 OPS, 7 HR
Going forward, Devers' quest to improve against lefties should be rooted in upgrading the walk (2.7 percent) and strikeout (19.2 percent) rates that he had against them in 2019. He can then focus on expanding his zone coverage, as he could really only make hard contact against lefties when he got his arms extended.
Should Devers do these things, he might take the next step toward becoming an MVP-caliber star.
Juan Soto, Washington Nationals: Keep Getting Better on Defense
Though Juan Soto is only 21 years old, he basically has nothing left to prove as a hitter.
In two seasons with the Washington Nationals, he has put up a .287/.403/.535 batting line with 56 home runs. He's done well against both righties (.977 OPS) and lefties (.849 OPS), and his clutch gene was on full display as he racked up a .927 OPS in the 2019 playoffs.
Soto also stole 12 bases last year, and he even got better on defense after rating as a liability as a rookie. As he told Sam Fortier of the Washington Post late last season, the latter was largely a function of knowing the ropes better: "[When I] just start moving with the counts, that helped me a lot."
But if there's one nit left to pick with Soto's defense, it's that he's better at coming in on balls than he is at going back on them. More specifically, he still has issues when he has to go back and to his right.
A minor weakness, to be sure. But if Soto can address it, his transformation into one of baseball's top superstars will be complete.
Ronald Acuna Jr., Atlanta Braves: Become a More Complete Slugger
There's very little, if anything, that Ronald Acuna Jr. can't do on the field.
He's a supreme athlete by any measure, and all he's done in two seasons with the Braves is rack up 9.9 WAR with Rookie of the Year, All-Star and Silver Slugger honors. Notably, he fell only three stolen bases shy of a 40-40 season in 2019.
That sounds nonsensical only until you realize that the 22-year-old hit just 22 doubles and two triples. It'd be easy to pin that on his occasional failures to hustle, but a potentially bigger issue might have been that Acuna was too often trying to hit home runs rather than simply trying to hit the ball hard.
In any case, we're harping on another relatively minor flaw. But if Acuna can make this one go away, he will claim a spot alongside Mike Trout, Cody Bellinger and Christian Yelich as one of baseball's all-around greats.