There aren’t any no-doubt, future All-Stars among the rookie position players who are likely to be on big-league rosters on opening day, but there are a number of hitters who should be solid contributors in 2021. Several rookies have already tasted success at the major league level and are good bets to continue their production (Randy Arozarena, Ryan Mountcastle, Nick Madrigal, Ke’Bryan Hayes), while others are mature, big-league ready prospects who had their arrivals delayed by the pandemic (Andrew Vaughn, Bobby Bradley, Alex Kirilloff, Taylor Trammell). Fantasy baseball owners need to be familiar with all these potential sleepers, whether they’re in redraft leagues or keeper/dynasty leagues.
The rankings below constitutes an assessment of 2021 impact and is limited to those players who are likely to open the season in the majors. As such, the bottom of the list includes players who may not have much value in a shallow redraft league. For those leagues, you may want to gamble on a higher-upside prospect in the hope that he gets a midseason promotion. I’ve included a half-dozen names to consider for this type of strategy
2021 MLB Top Prospects: Fantasy Baseball Rookie Hitter Sleepers
1. Randy Arozarena, OF, Tampa Bay. Arozarena had an historic post season in 2020 and enters this year with high expectations. There’s no doubt he’s an elite talent, but it’s unlikely he’ll produce at the level he did last fall. His electric bat speed produces elite exit velocity, and his good balance and direct swing path provide the leverage for his plus all-fields raw power. He destroys fastballs, but he’ll need to show he can hit breaking balls more consistently. I think ’21 will be a season of adjustments for Arozarena, but despite some ups and downs, he’s a good bet to hit .270 with 25-plus home runs and 20 stolen bases.
2. Ke’Bryan Hayes, 3B, Pittsburgh. Hayes impressed in a late-season call-up last year (.376 average with five home runs in 85 at-bats) and has continued to rake this spring. He’s in line to open the season as the Pirates’ starter at third base. Hayes has always had a plus glove, but last season he improved his balance that allowed him to more effectively use his lower half, creating a better bat path and increased bat speed. He was also able to maintain a solid contact rate, which bodes well for his future performance. In 2021, he could hit .275 with 25 home runs while batting in the top third of the Pittsburgh lineup.
3. Nick Madrigal, 2B, Chicago White Sox. Madrigal is returning from offseason shoulder surgery but made his Cactus League debut this week and could be ready for regular playing time shortly after the season begins. Madrigal is already one of the best pure hitters in baseball and performed as advertised in a late-season call-up last year (.340 average in 103 at-bats). When healthy, Madrigal displays elite contact skills and plus speed. He won’t hit for any power, but he could compete for a batting title while stealing 20-plus bags per season and playing plus defense at second base.
4. Andrew Vaughn, 1B, Chicago White Sox. Vaughn was considered the best hitter in the 2019 draft class, and despite very modest pro experience since then, has impressed the spring and looks like he’ll open the season as Chicago’s everyday DH. Vaughn’s hitting skills are as advertised: Compact stroke, above-average all-fields power, and good plate discipline. He still hasn’t fully tapped into his power potential, but he could hit .275 with close to 20 HRs and draw plenty of walks in ’21. If he can better use his lower body to create leverage and loft in his swing, he has the bat speed to eventually hit 30-plus home runs per year.
5. Ryan Mountcastle, OF, Baltimore. Mountcastle played well during his 2020 big-league debut (.333 and five home runs in 126 at-bats) and is projected to open the season in the Baltimore lineup. Mountcastle probably swings at too many pitches, although he doesn’t usually chase out of the zone. At the same time, he has great hand-eye coordination and makes contact at a very high rate due to an excellent swing path. His plus bat speed and good balance produce consistent hard contact. He can be a little too much on his front foot sometimes, which saps his power but he has the skills to hit .280 with 15-20 home runs. If he can be more selective and stay back a little more, he could eventually hit for more pop.
6. Dylan Carlson, OF, St. Louis. Carlson was initially overmatched in a 2020 big-league call-up but he improved at the tail end of the season and enters the spring favored to win a starting spot in St. Louis. The switch-hitting Carlson has a bit more power batting lefthanded, but he shows good bat speed and excellent hand-eye coordination from both sides. With solid pitch recognition and plus raw power, Carlson has the potential to hit .275 with 20-plus home runs and 10-15 stolen bases over a full season in the bigs. This year, he probably won’t reach those numbers, but a .260 average with 15 home runs and 15 stolen bases is possible.
7. Bobby Dalbec, 1B, Boston. Dalbec performed well in a late-season debut last year (.263, eight HRs in only 80 at-bats) and is likely to open 2021 as Boston’s starter at first base. Dalbec has plus raw power, but he swings and misses (even on pitches in the strike zone) at an elevated rate. He feasts on fastballs, and when he makes solid contact his plus bat speed produces good over-the-fence pop. His steep swing plane means that he won’t hit for average, but he could easily hit 20-25 HR over a full season — just be prepared for a batting average that sits close to the Mendoza Line.
8. Bobby Bradley, 1B, Cleveland. Bradley struggled in a short call-up during the 2019 season but enters this spring as the favorite to be Cleveland’s opening day first baseman. Bradley has a big swing that produces big power and big strikeout totals. This year he’s improved his swing path and is staying on the ball better. He’s also more agile and athletic at first base. It’s unclear whether he can sustain his current spring success, but his offseason adjustments give him some upside. If he can’t maintain his newfound swing and improved contact ability, he’ll probably play part time and put up average power numbers while hitting in the low .200s. If the changes stick, he could hit .260 with 20 HRs.
9. Cristian Pache, OF, Atlanta. Pache made a brief big-league debut in late 2020 and quickly showed that he is already one of the best defensive center fielders in the game. This spring he’s competing to be the Braves’ starting center fielder. Although he’s already an elite defender, Pache is still a work in progress offensively. He has good bat speed and solid raw power, but he sometimes loses his balance at the plate and doesn’t have a consistent swing path. Long-term, he the tools to be an above-average big-league hitter, but if he wins the CF job this season I expect him to post modest numbers in ’21 (.250 with 10 HRs and 10 SBs).
10. Alex Kirilloff, OF, Minnesota. Kirilloff is currently competing to be the Twins’ opening day left fielder and has shown flashes of his potential in Grapefruit League play. If I knew that he’d win the job, I’d rank him near the top of this list, but the playing time question pushes him down. Kirilloff has battled injuries throughout his pro career, but when healthy he’s a polished hitter with above-average power, good pitch recognition, and the bat speed to handle plus velocity. Whether he opens in the bigs or gets a midseason call-up, he should produce solid numbers (.270 with 15-20 HRs if he plays a full season) as a rookie.
11. Alejandro Kirk, C, Toronto. Kirk opened eyes in a short big-league cameo last season (.375 average, HR, just four strikeouts in 24 at-bats) and is off to a hot start this spring. It’s unclear whether he can win a roster spot to open the season but he looks like the catcher of the future in Toronto. Kirk has great plate discipline and a compact swing that produces above-average bat speed and power to all fields. He doesn’t have much experience against advanced pitching and his defense is average, but he has the tools to be a top-10 big-league catcher. If he gets 250-300 big-league at-bats this year, he could hit .270 and slug 10 or more home runs.
12. Ryan Jeffers, C, Minnesota. Jeffers had a solid big-league debut last season (.273, three HRs in 55 at-bats) and projects to be in a timeshare with Mitch Garver this season. Jeffers’ swing path and balance are average. He doesn’t have the leverage to drive the ball to the opposite field, but he has enough bat speed to clear the fence on his pull side. He shows solid pitch recognition and hand-eye coordination that should allow him to hit for a modest average. If he gets half the starts in Minnesota this season he should hit .250 with 10-12 home runs.
13. Isaac Paredes, 3B, Detroit. Paredes saw some big-league action last season and projects as the Tigers’ opening day third baseman. Paredes has good pitch recognition and hand-eye coordination that allows him to make consistent contact. It isn’t always hard contact because his balance and leverage are merely average. However, his swing path is direct, and once he gains some experience against big-league pitching he has the bat speed to drive the ball more if he can improve his balance. Over a full season in 2021, he should improve on last year’s numbers and hit around .260 with 10 HRs and a solid OBP.
14. Taylor Trammell, OF, Seattle. Trammell has been a highly ranked prospect for years but hasn’t yet turned his potential into performance. This could be the season that he finally turns things around. He’s off to a hot start this spring and is currently the frontrunner to be the Mariners’ opening day left fielder. I’ve watched Trammell adjust his mechanics every season for the past few years, but this spring he has better balanced and a more direct swing path that has allowed him to tap into his above-average raw power. He’s still a risky bet given that he has yet to demonstrate sustained success against advanced pitching, but his raw tools give him some upside. In a best case, he could hit .265 with 15-plus home runs and 15-plus stolen bases in 2021.
15. Jonah Heim, C, Texas. Heim will probably be the Rangers’ No. 2 catcher this season and could put up solid offensive numbers. The switch-hitting Heim has good plate discipline and makes consistent contact. He doesn’t have the leverage in his swing to hit for much power, but he can spray line drives from foul line to foul line. In a part-time role he could hit .270 with around eight HRs.
16. Zack McKinstry, 2B/3B/OF, Los Angeles Dodgers. McKinstry is expected to fill the utility role vacated by Enrique Hernandez and should see regular at-bats. McKinstry has average tools but shows good plate discipline and solid contact ability. His average bat speed means that he won’t hit for much power, but he could put up solid numbers (.270 average, .330 OBP, around 10 HRs) if he gets 300-400 at-bats.
17. Tyler Stephenson, C, Cincinnati. Stephenson looked good in limited big-league action last season (.294 with two HRs in 17 at-bats) and projects to be the Reds’ No. 2 catcher this year. Stephenson has a simple load and good pitch recognition that should allow him to hit for average and get on base. He doesn’t use his lower half as much as he could, but he is strong enough to generate good bat speed without lots of pre-swing movement. His balance isn’t ideal, which means that he doesn’t have much opposite field power, but he has above-average pull-side pop. If he gets 150-200 at-bats, he should hit around .265 with close to eight HRs.
18. Leody Taveras, OF, Texas. Taveras got some big-league experience late last season (.227 average, four HRs in 119 at-bats) and is the front runner to be the Rangers’ starting center fielder in 2021. The switch-hitting Taveras has elite tools but hasn’t yet developed the skills necessary to succeed at the major league level. He’s more fluid hitting righthanded, but he is prone to chasing pitches out of the zone and his swing path is inconsistent. He’s still developing and his raw power has increased, so he could eventually be an average big-league center fielder, but I’d be surprised if he hits above .250 or logs more than 10 HRs with Texas this season.
19. Pavin Smith, OF, Arizona. Smith will likely break camp as the team’s starting right fielder, but how long he sticks in that role depends on how quickly Kole Calhoun recovers from knee surgery. Smith is a polished hitter who should produce even in limited action (.270 with a good OBP). At the moment, he doesn’t have the leverage in his swing to hit for power, but he has the bat speed and strength to develop average power as he matures.
20. Brent Rooker, OF, Minnesota. If Kirilloff falters, Rooker could win a starting spot or a platoon role in Minnesota. Rooker doesn’t have good balance, so he’s more of a timing hitter who crushes the ball when he’s on time and swings through it when he’s not. His power is legit, so he could produce a handful of home runs, but he’ll struggle to hit more than .240.
21. Dom Nunez, C, Colorado. Nunez should break camp as the No. 2 catcher for the Rockies. He doesn’t have a lot of offensive upside, but playing in Colorado will give his stats a boost. Nunez doesn’t have great balance and struggles against breaking balls, but he has the bat speed and strength to drive the ball to the pull side. If he gets 200-250 at bats, he could hit about .220 with close to 10 HRs.
22. Jazz Chisholm, 2B, Miami. Chisholm had a lackluster debut in 2020 after initially opting out of the season (.161 average with two HRs in 56 at-bats) and is battling for the second base job this spring with Miami. He may win the job, but I’m not sure he can hold it. Chisholm doesn’t have good balance or leverage in his swing, which results in lots of weak contact. He has the raw tools to be a successful big-leaguer, but he has a lot of work to do on his mechanics.
23. Ha-Seong Kim, SS/3B, San Diego. Kim was signed as a utility player and he may get that chance, but I just don’t see him beating out Jurickson Profar for playing time and he has looked overmatched in early spring games. At this point he doesn’t look like a significant contributor on offense in 2021.
24. Akil Baddoo, OF, Detroit. Baddoo has raked this spring and may make the Tigers roster after being selected as a Rule 5 pick this season. He’s made headlines, but if he makes the roster he’ll be a fifth outfielder…and fifth outfielders don’t play much.
Best Bets for Midseason Impact
1. Wander Franco, SS, Tampa Bay. He’s the best prospect in baseball and has played well this spring. It will be hard for the Rays to keep him on the farm if he gets off to a hot start.
2. Jared Kelenic, OF, Seattle. After beginning camp with a shot at being the Mariners’ opening day left fielder, Kelenic sustained a mild leg injury that probably now has him ticketed for the minors at the start of the season. If Trammell stays hot, Kelenic may not be promoted until midseason, but if Trammell struggles or doesn’t win the job, Kelenic could be in Seattle in April or May.
3. Luis Campusano, C, San Diego. Campusano could make the opening day roster given Austin Nola’s injury, but the rookie is more likely to get additional minor league seasoning before returning to the bigs. He’s an elite hitter and should be back in San Diego by midseason.
4. Joey Bart, C, San Francisco. Posey is the starter and Bart struggled last season, but the rookie has played well this spring and is too good to remain in the minors for very long.
5. Brandon Marsh, OF, Los Angeles Angels. Marsh has been dealing with a shoulder issue this spring and will probably begin the season in the minors. Given the state of the Angels makeshift outfield, he probably won’t stay there long.
6. Josh Jung, 3B, Texas. Jung impressed in big-league camp before being sent down last week. The Rangers’ third base depth is thin, and a hot start by Jung could get him a quick call back to Texas.