Every single player in Fantasy Baseball has bust potential -- yes, even Juan Soto and Ronald Acuña and Mike Trout can go wrong. Every player has injury risk, and down years can happen to anyone at any time, even without warning.
But that's not to say every player has the same amount of bust potential. It goes without saying that some players have more ways for things to go wrong for them, but some of them also have so much potential that you can't just ignore them. You need to embrace risk on your Fantasy team to have a chance to win -- if every player on your roster just hits their 50th percentile projected outcome, you're probably going to finish in sixth place. You need big hits, and sometimes, that means taking big swings.
We talked about players with boom-or-bust potential on Monday's episode of the Fantasy Baseball Today podcast, which you can listen to below -- and head here to subscribe at Apple, Spotify, or wherever you get your podcasts:
Here are my picks for the biggest boom-or-bust players for the 2021 season, and what I think their chances of hitting either outcome are. You probably don't want an entire lineup full of these guys, but you'll need to take a chance on at least a few of them if you want to bring home a title.
The All Boom-or-Bust Team
I've lost a lot of faith in Sanchez over the last few seasons. He arguably has as much upside as anyone at the catcher position, and he's still the only player at the position with the potential to become the first since Javy Lopez in 2003 to hit 40 homers. But there are too many times when it just seems like his swing is broken -- his sub-.200 BABIP in two of the last three seasons is harder to write off when you see his sub-17% line drive rate and super-high infield flyball rate. Sanchez has also had some trouble staying healthy over the last few seasons, so there are non-performance-related questions, too. Sanchez is a classic boom-or-bust player, and given that he plays a position with so few potential impact bats, it's easier to justify taking on that risk here.
When my first round of rankings came out in early February, I had Bellinger as a borderline first-rounder, but he's been slipping to the low teens ever since. Bellinger hasn't played in a game yet this spring, and he only started facing full-speed pitching last week as he recovers from shoulder injury. If he's fully recovered, I think Bellinger has a pretty good chance to get back to being an elite hitter -- despite his struggles in 2020, he sustained his plate discipline gains from his breakout 2019, a big part of his success. However, shoulder injuries are tough for hitters, and it may take a little while for him to get back to full strength. I don't mind Bellinger with a late second-round pick, because he's one of the rare players with 45-homer potential and 15-steal potential. But there's a lot of ways that this could go wrong for him.
Hiura needs to find a way to fix his contact issues because he had one of the lowest contact rates in baseball in 2020. When he does make contact, good things tend to happen for Hiura, who has legitimate five-category potential if everything clicks. However, he got exposed last season, and the quality of contact took a step back along with the plate discipline. I'm optimistic about Hiura's chances, but I'll admit, it's not like I can point to any one thing as proof -- I just believe in the talent. Sometimes you've gotta go with your gut, but if your gut doesn't agree with me, I can't argue with you.
A career .279/.354/.399 hitter in 461 minor-league games, Hayes came up and crushed the ball in 24 games in 2020, hitting .376/.442/.682 with sterling batted-ball quality to back it up. The scouting reports and prospect rankings usually suggested Hayes had more potential than his numbers showed as a prospect, and it's possible everything clicked for him in the alternate site and he truly made a leap. If that was the case, he could be a five-category contributor and a potential elite Fantasy 3B. Or, he just had a good few weeks and played over his head. Scott White is buying into Hayes, and a hot start to his spring should make him more confident, but I'm a little bit more skeptical.
Mondesi could single-handedly help you compete in stolen bases this season -- he has 67 in 161 games over the last two seasons, and the averaged sixth-place finish in 2019 12-team Roto leagues had 108 steals. And this isn't quite a Billy Hamilton situation, as Mondesi does have 15 homers, 84 RBI and 91 R over that stretch, too. However, he's got serious plate discipline issues, and it's not inconceivable that the bottom falls out and he sports a .270 OBP this season. The Royals are suddenly pretty competent offensively, so he might bat seventh or lower in the lineup, which could cost him as much as 100 PA compared to the leadoff spot. Mondesi's defense should be good enough to keep him in the lineup even if that worst-case scenario does come to pass, but he could be a drag in four categories. Are steals really that hard to find?
What does the upside look like for Luis Robert? Well, here's his 150-game pace based on how he played in August of last season:
- .298/.356/.660 with 52 HR, 17 SB, 110 runs, and 115 RBI.
And what does the downside look like? Well, here's his 150-game pace from September/October:
- .136/.237/.173 with 7 HR, 33 SB, 72 R, 46 RBI
OK, his upside probably isn't actually that high, and his downside isn't actually that low. But Robert could legitimately be one of the best players in Fantasy, a no-doubt-about-it first-rounder with five category appeal. Or he could flirt with the Mendoza line and hack his way to the bottom of the White Sox lineup, pushing him outside of the top 100 in ADP this time next year. Both are on the table.
Stanton has lost zero bat speed entering his 30s -- he is the only player in the majors with a batted ball over 120 mph over the last two seasons (he has two), and he added another in a spring game Monday. If he's on the field, he should be one of the best power hitters in the game, with legitimate 50-plus homer potential. Of course, he has played just 41 games over the last two seasons, and his injury history stretches as far back as his MLB career. If Stanton stays healthy, he should be a top-25 hitter, but he hasn't done that since 2018.
Arozarena has a very similar profile to Robert, and in a best-case scenario, he'll be a game-changing power/speed combo. However, he didn't have anywhere near the kind of power in the minors that we saw in 2020 -- he had 17 homers in 43 games between the regular season and postseason. There's also potentially enough swing-and-miss in his game to derail him even if the power is real -- especially because he plays for the Rays, a team that is not afraid to put even a promising young player into a part-time role if they think it maximizes their chances of winning.
I kind of think Scherzer is less of a risk than the general consensus -- he missed just one start in 2020, with a hamstring issue, and he's looked like his vintage self in spring, sporting a 2.08 ERA with 14 strikeouts and only two walks in 8.2 innings. Of course, he is a soon-to-be 37-year-old who dealt with back and neck injuries in 2019 and wasn't his usual self in 2020. If he's healthy, Scherzer should be an ace -- I've got him ranked No. 4 among SP -- but he's also well past the age where the bottom could fall out.
Snell's ERA by season for his career looks like this: 3.54, 4.04, 1.89, 4.29, 3.24. Oh, and he's had elbow issues over the last two years and has thrown more than 180.2 innings just once. The Rays limited Snell's innings and exposure to the lineup a third time in a way that was pretty frustrating for Fantasy, but it's worth asking whether those limitations helped Snell's ratios and his health. We'll find out this season, as the Padres are likely to have a looser leash with their newly acquired ace. I'm wary of paying full price for Snell, but I can see the appeal.
Here's the last two seasons for Burnes:
- 2020: 59.2 IP, 240 BF, 2.11 ERA, 1.022 WHIP, 36.7% K rate, 10% BB rate, 0.3 HR/9
- 2019: 49.0 IP, 235 BF, 8.82 ERA, 1.837 WHIP, 29.8% K rate, 8.% BB rate, 3.1 HR/9
So, basically identical sample sizes with widely divergent results. He'll definitely get a lot of strikeouts, but that's about all you can say definitively. However, Burnes did tweak his pitch mix last season for the better, so I'm optimistic about his chances of pitching closer to his 2020 form.
The risk became even more acute when Strasburg left Sunday's spring start with a calf injury. Ironically, despite Strasburg's extensive injury history, he's never been on the IL for a lower-body injury. He's coming back from carpal tunnel surgery and now has this injury to contend with. When he's right, Strasburg is one of the best pitchers in baseball, but you can't exactly trust him when he's not currently … y'know … right.
The assumption from most is that Lamet will be very good as long as he's healthy, with the lingering elbow/bicep concerns from late last season looming over him deep into spring. I'll just point out that, while Lamet was awesome in 2020, he had 187.1 innings of a 4.37 ERA between 2017 and 2019. He's a two-pitch pitcher with a history of command issues, so he's no guarantee to be an ace even if that elbow doesn't become an issue again.
I'm actually less concerned about Diaz than pretty much anyone else, but Frank Stampfl had him as the poster boy for the boom-or-bust category on the podcast, so I'll include him here. He's really only had one bad season -- though in fairness, that was a whopper, as he had a 5.59 ERA and 1.38 WHIP in 2019. The bigger concern might be that short leash the Mets had with him last season -- he went from July 25 to Aug. 28 without getting a save chance in a final inning of a game, and then didn't get another chance until Sept. 9 after blowing another one Aug. 30.
If Yates is healthy, he'll probably be one of the best relievers in baseball -- he had a 1.67 ERA with 191 strikeouts between 2018 and 2019. However, he was never right in 2020, ultimately requiring season-ending elbow surgery. He should get plenty of opportunities to close out games for the Blue Jays, but if he can't do the job, Jordan Romano to pick up the ball if the 33-year-old Yates stumbles.