| Name | Pos | Team | Age | Injured List |
|---|---|---|---|---|
| Tyler Stephenson | C (1B) | Cin | 25 | |
| Triston Casas | 1B | Bos | 21 | |
| Rhys Hoskins | 1B | Phi | 28 | August 26, 2021:10 Day IL-Lower abdomen sugery - out for season |
| Nick Pratto | 1B | KC | 22 | |
| Brent Rooker | 1B (OF,DH) | Min | 26 | |
| Gavin Sheets | 1B (OF,DH) | ChA | 25 | |
| Andrew Vaughn | 1B (OF,DH) | ChA | 23 | |
| Keston Hiura | 2B (1B) | Mil | 25 | |
| Jonathan India | 2B | Cin | 24 | |
| Xander Bogaerts | SS (DH) | Bos | 28 | |
| Brian Anderson | OF (3B) | Mia | 28 | August 31, 2021:10 Day IL-Left shoulder subluxation |
| Harrison Bader | OF | StL | 27 | |
| Byron Buxton | OF | Min | 27 | |
| Kole Calhoun | OF (DH) | Ari | 33 | |
| Jake Fraley | OF (DH) | Sea | 26 | |
| Riley Greene | OF | Det | 20 | |
| Austin Hays | OF | Bal | 26 | |
| Pedro Leon | OF | Hou | 23 | |
| Josh Lowe | OF | TB | 23 | |
| Wil Myers | OF | SD | 30 | |
| Marcell Ozuna | OF | Atl | 30 | May 26, 2021:10 Day IL-Fractured fingers, left hand |
| Alex Verdugo | OF | Bos | 25 | |
| Johnny Cueto | SP | SF | 35 | September 01, 2021:10 Day IL-Strained right elbow |
| Josh Fleming | SP (RP) | TB | 26 | |
| Hunter Greene | SP | Cin | 22 | |
| Vladimir Gutierrez | SP | Cin | 26 | |
| Sean Manaea | SP | Oak | 29 | |
| Alek Manoah | SP | Tor | 23 | |
| Eduardo Rodriguez | SP | Bos | 28 | |
| Stephen Strasburg | SP | Was | 33 | June 02, 2021:10 Day IL-Neck strain |
| Justin Verlander | SP | Hou | 38 | February 27, 2021:60 Day IL-Recovery from right elbow surgery |
| Aroldis Chapman | RP | NYA | 33 | |
| Luis Garcia | RP (SP) | Hou | 24 | |
| Ian Kennedy | RP | Phi | 36 |