Our annual attempt to rank all of the year's graduated rookies based on their long-term career value is more difficult than usual.
The top spot is easy. Rays shortstop Wander Franco went from baseball's No. 1 prospect to reaching base in 43 consecutive games, tying Frank Robinson's record for big leaguers age 20 or younger.
But after Franco, there weren't many obvious choices. Mariners outfielder Jarred Kelenic entered the year ranked No. 4 on MLB Pipeline's Top 100 Prospects list, then slashed .151/.236/.272 with a 30 percent strikeout rate in his first three months in the Majors. Many of 2021's best rookie performers were relatively old, while many of its top prospects struggled in their first extended taste of the Majors.
As always with these rankings present-year performance does matter, as does past track record and future projections. Age is a significant factor, so we've included each player's seasonal age as of July 1, and it's no coincidence that the two youngest players rank 1-2 and four of the top five are 22 or younger.
This list considers only graduated rookies, meaning they've exceeded 130 at-bats, 50 innings or 45 days of active service time in the big leagues. Giants catcher Joey Bart (No. 16 on the current Top 100) and Red Sox outfielder Jarren Duran (No. 25) are close to the limits but still have prospect eligibility remaining, so they're not included.
1. Wander Franco, SS, Rays (age 20)
Franco slashed .288/.347/.463 in 70 games for an OPS+ of 129, a figure exceeded by just 10 rookies his age or younger with at least as many plate appearances (308) since 1900: Mike Trout, Ted Williams, Fernando Tatis Jr., Rogers Hornsby, Ronald Acuña Jr., Frank Robinson, Juan Soto, Tony Conigliaro, Carlos Correa and Jason Heyward.
2. Jarred Kelenic, OF, Mariners (age 21)
Kelenic rallied to hit .248/.331/.524 in the final month, and he's still a 21-year-old center fielder who possesses at least 25-25 upside.
3. Ke'Bryan Hayes, 3B, Pirates (age 24)
Wrist and hand injuries derailed the preseason National League Rookie of the Year favorite, a future Gold Glover with a quality bat and developing power.
4. Keibert Ruiz, C, Nationals (age 22)
Part of the Trea Turner/Max Scherzer trade with the Dodgers in July, Ruiz is a switch-hitter with advanced contact skills, burgeoning power and a chance to be a solid defender at a premium position.
5. Dylan Carlson, OF, Cardinals (age 22)
A switch-hitter with the chance to stick in center field with at least solid tools across the board, Carlson batted .277/.343/.505 with 11 homers in 61 second-half games to spark St. Louis to a playoff berth.
6. Alek Manoah, RHP, Blue Jays (age 23)
Manoah dominated with his fastball and slider in his debut, leading all rookies (minimum: 100 innings) in opponent average (.191) and ranking second in ERA (3.22) and strikeout percentage (27.7).
7. Trevor Rogers, LHP, Marlins (age 23)
Rogers' superlative changeup helps his fastball play up and allowed him to top all rookies in ERA (2.64) and strikeout percentage (28.5). The only rookies with as many innings and a lower ERA in the past 25 years are José Fernández and Walker Buehler.
8. Andrew Vaughn, OF/1B, White Sox (age 23)
The No. 3 pick in the 2019 Draft and one of the better college hitters in recent Drafts, Vaughn reached Chicago after just 55 games in the Minors and played regularly for a division champion while learning a new position on the fly.
9. Randy Arozarena, OF, Rays (age 26)
The only 26-year-old to rank in the top 10 in the seven years we've done this list, Arozarena followed up one of the best postseasons ever by becoming the 11th rookie ever to record a 20-20 season.
10. Jose Barrero, SS/OF, Reds (age 23)
If he can develop more patience at the plate, Barrero could hit for average and power while providing solid defense at shortstop or in center field.
11. Logan Gilbert, RHP, Mariners (age 24)
Gilbert already has one of baseball's best four-seamers, possesses three other promising pitches and commands the strike zone. He easily topped all rookies with a 4.6 K/BB ratio.
12. Alex Kirilloff, OF/1B, Twins (age 23)
Injuries hampered Kirilloff's rookie season and much of his pro career, but his one fully healthy year (.348/.392/.578 in Low-A and High-A in 2018) testifies to his considerable offensive ceiling.
13. Triston McKenzie, RHP, Cleveland (age 23)
Yet another homegrown pitching success story for Cleveland, McKenzie, who nearly threw a perfect game in August, could take another step forward if he throws strikes like he did in the Minors and in his 2020 debut.
14. Ian Anderson, RHP, Braves (age 23)
A postseason hero last October, Anderson has the stuff to be a frontline starter if he can improve his fringy control.
15. Tarik Skubal, LHP, Tigers (age 24)
Why Skubal over teammate Casey Mize, the No. 1 overall choice in 2018? Mize's splitter and command haven't been as sharp as they were in the past, while Skubal has shown a greater ability to miss bats.
The next 15:
16. Casey Mize, RHP, Tigers (age 24)
17. Shane McClanahan, LHP, Rays (age 24)
18. Josiah Gray, RHP, Nationals (age 23)
19. Luis Patiño, RHP, Rays (age 21)
20. Jazz Chisholm, 2B/SS, Marlins (age 23)
21. Tyler Stephenson, C/1B, Reds (age 24)
22. Jonathan India, 2B, Reds (age 24)
23. Michael Kopech, RHP, White Sox (age 25)
24. Nate Pearson, RHP, Blue Jays (age 24)
25. Garrett Crochet, LHP, White Sox (age 22)
26. Luis Garcia, RHP, Astros (age 24)
27. Ryan Mountcastle, 1B/OF, Orioles (age 24)
28. Jesús Sánchez, OF, Marlins (age 23)
29. Alejandro Kirk, C, Blue Jays (age 22)
30. Emmanuel Clase, RHP, Cleveland (age 23)