Every year, there are those rookies who we expect to make a splash right away. In 2020, it was Luis Robert, Kyle Lewis, Alec Bohm, and Sixto Sanchez.
Below are 10 of the American League's potential top rookies for 2021, both at the dish and on the mound. I've ranked them in order of how quickly I expect them to make an impact.
While some might take a few weeks or a couple of months to get there, all of these prospects are ready to be difference-makers in fantasy lineups right along with the real-life lineups they burst into.
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Randy Arozarena (OF, TB)
When the Tampa Bay Rays traded former first-round selection Matthew Liberatore to St. Louis in the trade that brought Randy Arozarena to Tampa, prospect evaluators were given a clue that they were sleeping on "Dandy Randy". After his 2020 playoff outburst, there can be no doubt that Arozarena should have been higher up the industry Top 100 lists heading into the 2020 season.
Arozarena is ready to make his impact felt in redraft leagues immediately. Just looking ahead to 2021, Arozarena is projected as a 20/20 player in RotoBaller’s premium ATC projections. Nick Marino’s Cutter projections are even more generous, giving Arozarena a projected 30 home runs in 2021. If you consider his productivity in dynasty leagues beyond 2021, Arozarena is potentially a Top-30 dynasty asset due to his five-category potential. He’s the AL’s next budding superstar, and the odds-on favorite to win AL Rookie of the Year in 2021.
Alex Kirilloff (OF, MIN)
Looking for a hitter who could break out for 30+ home runs in 2021? Look no further than the Minnesota Twins’ Alex Kirilloff. Kirilloff, 23, was Minnesota’s 1st round pick out of high school in the 2016 draft. He then missed a year of development in 2017 after undergoing Tommy John surgery. Then, in 2018, he exploded, with his plus hit tool leading the charge.
In his first taste of full-season ball in 2018, Kirilloff posted a gaudy 176 wRC+. For fantasy owners, his .274 ISO pointed to the future power potential in his bat. Kirilloff has performed admirably since, showing a propensity both for making contact and driving the ball hard when he connects. Our ATC projections show him posting a .273/.325/.438 slash line in the Majors in 2021, more than enough production for a role as Minnesota’s everyday left fielder. While the team has chosen to start him out in the alternate site to begin the year, I really believe that Kirilloff will be up soon and ready to contribute to your fantasy squads.
Nick Madrigal (2B, CHW)
The White Sox minuscule warrior is poised to take a leap in his second major league season. Nick Madrigal was the club’s first-round selection out of Oregon State University in the 2018 draft. He was drafted on the prowess of his hit tool, which leads him to post contact rates in the Wade Boggs/Tony Gwynn stratosphere. In line with this expectation, Madrigal posted a .309 batting average throughout his first two years in the minor leagues.
For dynasty leaguers, Madrigal is an excellent building block. He serves as a great batting average buddy in old-school roto leagues that use batting average. His extreme contact rate should always give him a reliable batting average floor. For OBP leagues, he’s still valuable as that same contact rate also buoys his on-base skills. Additionally, he has flashed the speed and baserunning acumen in the minors to chip in an annual 20-30 stolen bases at the big league level. With batting average and speed locked in, Madrigal affords dynasty owners the ability to speculate in other areas on the hitting side of their roster.
Casey Mize (SP, DET)
This former War Eagle was the first overall pick in the 2018 Rule 4 draft. During his brief time in the minors, Casey Mize has displayed the tantalizing stuff that makes a future frontline starter. His brief 2020 MLB debut was rocky, to say the least. Hitters were able to square up both his sinker (.610 slugging against) and his cut fastball (.695 slugging against), pitches that he threw 46.6% of the time in his debut season.
So why the reason for optimism with Mize in 2021? The good news is that his sinker and cutter are only two-fifths of his pitching arsenal. His four-seam fastball was both a whiff (27.9% whiff rate) and flyball (28-degree average launch angle) generator in the bigs last year. His splitter is a double-plus offering, averaging nearly 5 inches of drop beyond the average splitter in the MLB last season. And his curveball shows good two-plane tilt at times, racking up a 44% whiff rate in 2020 despite limited usage (10%) of the pitch.
The best news regarding Mize, however, is that his arm looks healthy this spring. He’s throwing every pitch in his mix, and his fastball is touching 98 mph. If his fastball velocity can sit around 95, and he can lean on the four-seamer more, his whole arsenal will play up. He's also secured himself a spot in the opening day rotation:
.@Casey_Mize struck out nine batters in just four innings of work tonight! ? pic.twitter.com/7uuOvt1Mfu
— Detroit Tigers Player Development (@RoadtoDetroit) March 26, 2021
Tarik Skubal (SP, DET)
Not to be overshadowed by the other young Motor City Kitty hurlers, left-hander Tarik Skubal has earned a spot on the Tigers’ Opening Day roster with his solid performance this spring. Skubal, 24, slipped under the radar in the 2018 draft. Between attending a lesser-known school (Seattle University), and missing a season due to Tommy John surgery, Skubal slid down to the 9th round where Detroit shrewdly scooped him up.
Skubal has been awfully impressive during his professional career thus far. His 2.59 FIP over 15 starts for High-A Lakeland in 2019 was his WORST performance in the minor leagues. A four-seam fastball sitting 94 mph is his bread and butter. It features elite (98%) active spin rate, allowing it to play up in the zone against MLB hitters. He pairs it with two shapes of breaking balls, with a harder slider that flashes plus the better offering.
Skubal modified his changeup grip this offseason, hopefully providing him with a tantalizing weapon to employ against right-handed batters this season. It could be the difference between him succeeding in the rotation as opposed to the bullpen in 2021.
Garrett Crochet (RP, CHW)
Tall drink of water was the White Sox 1st round selection out of the University of Tennessee in last June’s abbreviated MLB Draft. After a bit of time dominating the competition at the Schaumburg alternate site, Crochet was called up to make his MLB debut on September 18. He proceeded to uncork a number of fastballs which just made professional hitters look foolish. He threw his four-seamer 84% of the time in his 2020 debut, averaging 100.1 mph on the pitch. MLB batters hit .167 against the pitch, with a 40% whiff rate. And if you look at his location chart with the pitch, he was basically living in the middle of the zone with it:
A friend of mine put an Aroldis Chapman comp on Crochet, and it’s hard to unsee it once you get that image in your head. Similar to Chapman, fantasy owners will be rooting that Crochet gets his chance to try and establish himself as a starter at the MLB level. It will not happen this year, however, as new White Sox manager Tony La Russa has said that Crochet will be solely a bullpen asset in 2021.
Bobby Dalbec (1B, BOS)
"Big Shot Bob” has impressed this spring, leading all of MLB with seven spring training home runs. He has flashed 70 raw power throughout his minor league career. The all-fields power shown in his 2020 MLB spray chart attests to how much pop Dalbec has in his bat:
The test for Dalbec in 2021 will be to marry this elite raw power with enough patience at the plate to ensure that he remains a positive run producer in the Boston lineup. He’s a patient hitter, and his 10.9% walk rate in the bigs last year is a positive sign. And he can improve on that measure in 2021, as his Chase rate of 33.5% is about five percentage points above the MLB average. If he can reign in that approach a little more, and continue making hard contact, Boston can probably live with a strikeout rate near 35%.
Taylor Trammell (OF, SEA)
Taylor Trammell has been an impact prospect for several years now. In 2019, he was the MVP of the Futures Game, displaying a tantalizing blend of all five tools against the best competition in the minor leagues at that time:
ICYMI: 2017 Dragons Outfielder Taylor Trammell (@Taytram24) was named MLB All-Star Futures Game on Sunday after going 2-2 with a Home Run and a Triple! Highlights ? @Reds pic.twitter.com/dB7Vs5E2rU
— Dayton Dragons (@DragonsBaseball) July 17, 2018
Trammell still seems to be in the pole position for Seattle’s starting left field job in 2021. Other young outfield studs Jarred Kelenic and Julio Rodriguez are also considerations for the Mariners. However, Trammell is a little more advanced than either of those players. He also presents a steady game that would be useful for any franchise. He’s got the ability to put together above-average plate discipline, raw power, speed, and defense. For fantasy leaguers, that makes him a potential above-average contributor across the board in all categories. He just needs the opportunity to show what he can do.
Ryan Mountcastle (1B, BAL)
Mountcastle was drafted out of the prep ranks by the Orioles in the first comp round of the 2015 MLB Draft. Praised for his hit tool throughout his minor league career, Mountcastle displayed a really impressive ability to make productive contact using an aggressive approach against MLB pitching in his 2020 debut:
Not only is Mountcastle an aggressive, high contact hitter, but he also has enough power to punish the ball when he makes contact, resulting in the ability to hit for extra bases. He might have a hard time becoming an elite home run hitter with his current approach. However, we have seen examples of some batters with elite contact rates and an aggressive approach being able to make an adjustment to sell off some contact for pull-side power (see Jose Ramirez). Either way, Mountcastle’s plus batting average and 20 home run floor will play in traditional roto leagues as soon as 2021.
Jarred Kelenic (OF, SEA)
He is likely to start the 2021 season at the alternate site unless he signs a team-friendly contract extension with the Mariners prior to the start of the season. Either way, Jarred Kelenic is a player you have to keep on your radar for redraft leagues in 2021. Hold back a little FAAB for his inevitable late April debut, as he is the type of five-category talent that can help push you to a title.
When Kelenic was coming out of high school in the 2018 draft, my only question mark regarding his profile was whether he’d hit for enough power to become a regular all-start caliber offensive producer. Well, that was a whiff on my part. Kelenic has done nothing but add good weight since his draft year, and that muscle has carried over into power in game situations:
Jarred Kelenic teed off today. pic.twitter.com/KVfXVIW3Aj
— MLB Pipeline (@MLBPipeline) March 22, 2021
It seems as though that the question now is whether the added muscle will hamper his ability to steal bases or cover center field in the future. Kelenic is such a natural athlete and above-average worker at his craft, that I wouldn’t be worried too much about either concern. He’s got potential plus tools across the board, with near-elite makeup as well.
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