Three Rookie Sleepers that Debuted in Late 2020

January 17, 2021

Michael's analysis of rookies who debuted last season and could break out in 2021 fantasy baseball. These players could be draft sleepers to target.

For a wide variety of reasons, 2020 was an unusual season for baseball. But out of these unusual situations came some opportunities for top-tier prospects to get a shot at the big leagues.

Now prospects that made a splash in their debuts like Ke'Bryan Hayes or Tanner Houck will be garnering the interest of many a fantasy manager heading into 2021. But while they focus on those players, that leaves the door open for smart managers to take advantage of slightly-less desired prospects that could be in a position to make just as big an impact in fantasy, if not more. We're going to take a look at three of these guys who will look to make a splash in 2021: Twins outfielder Brent Rooker, Red Sox first baseman Bobby Dalbec and Indians pitcher Triston McKenzie.

All three of these players are projected to crack the Opening Day roster with their teams, and all three of them are currently being drafted on average in the 18th round or later. If you're looking for the most bang for your buck in 2021, take a look at these rookies.

Brent Rooker (OF, MIN)

ADP 652

2020 stats: 7 G, .316/.381/.579, 1 HR, 5 RBI, 5:0 K:BB

Rooker is a guy that I've been pretty high on since his first season of pro ball. At Triple-A in 2019, Rooker hit a career-high .282 with 14 homers, a .530 slugging percentage and a career-high .399 on-base percentage over 67 games. His strikeout rate that year ballooned to 33.8 percent, but he also managed a career-best 12.8 percent walk rate.

Of the three guys on this list, Rooker ended up having the most limited playing time after a fractured forearm cut his season short after just seven games. Looking at some of his numbers, you can see some positive aspects albeit with the disclaimer of small sample size. His 23.8 percent strikeout rate pretty closely lined up with his rate in the minors, and his 12.9 percent swinging-strike rate was lower than in any of his previous seasons. He was also making solid contact in his limited stint, posting a 14.3 percent barrel rate and 50 percent hard-hit rate. But again, it's hard to draw solid conclusions based on his limited playing time.

Rooker is currently projected to make the Opening Day roster as likely a fourth outfielder or backup first baseman. He should hit for a good average and be a good source of runs thanks to his ability to get on base. Based on potential playing time he'll probably hit closer to 10 to 15 homers, but he could get up to 15 to 20 home runs if someone like Byron Buxton or Miguel Sano spends extended time on the Injured List. The decision not to retain Eddie Rosario and still undetermined contract issue for Nelson Cruz could open the door even wider for him to start. He'll be a solid late-round lottery pick in 12-team and deeper leagues, and he could be a good waiver-wire injury fill-in for 10-team leagues.

Bobby Dalbec (1B, BOS)

ADP 269

2020 stats: 23 G, .263/.359/.600, 8 HR, 16 RBI, 39:10 K:BB

After coming up through Boston's farm system as a third baseman, Dalbec now projects to be the Opening Day first baseman for the Red Sox with Rafael Devers manning the hot corner. Dalbec slugged his way through the upper levels of the minors, hitting 32 home runs with 109 RBI in 2018 and 27 home runs with 73 RBI in 2019. But that power comes with a high strikeout rate, as he sports a 29.8 percent strikeout rate over four seasons in the minors.

That high strikeout rate showed up in his stint with Boston this season, with a whopping 42.4 percent strikeout rate while his 21.2 percent swinging strike rate was his second-highest mark of his professional career. But what also showed up was his power, as he was one of four players that debuted in 2020 to hit eight or more home runs — and he was the only one to do so in fewer than 100 plate appearances. Don't expect much better than a .250 average from Dalbec — .257 is his best mark in full-season ball — and he might not get a ton of RBI to start the year as Fangraphs currently projects him to hit in the bottom third of the lineup. But for where he is currently going in drafts, he's one of the better options for managers chasing home runs in later rounds.

Triston McKenzie (SP, CLE)

ADP 173

2020 stats: 8 G, 6 GS, 33.1 IP, 2-1, 3.24 ERA, 0.900 WHIP, 42 K

And now we reach McKenzie, who is currently being drafted the highest out of the three on this list. He is also the most heralded prospect of the three, having been ranked as a top-100 prospect from 2017 through 2019. He missed the 2019 season due to strains of his lat and pectoral muscles, but his career 30.4 percent strikeout rate, 0.997 WHIP and 2.68 ERA over four seasons in the minors was enough to convince Cleveland to give him a shot in 2020.

Despite missing a year, McKenzie looked good in his debut campaign — going 2-1 with a 3.24 ERA, 0.900 WHIP and an 11.34 K/9. His 33.1 percent strikeout rate was also the highest among rookie pitchers with at least 30 innings, and his 12.4 percent swinging strike rate was his best mark since 2017 at High-A. The biggest concern is that his ERA might rise this year, as his 3.90 FIP and 3.60 xFIP suggest McKenzie got a little lucky at times, and batters were able to make solid contact off him to the tune of a 12 percent barrel rate and 36 percent hard-hit rate. But managers who are willing to risk his ERA going up will be rewarded by a plethora of strikeouts —especially pitching in a division with three of the top 13 teams in the league in batter strikeouts in 2020. McKenzie should be a solid No. 3 starter in almost any format.

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