| Player | Team | Action | Details | |
|---|---|---|---|---|
| Craig Stammen | Nixon's Nasty Ninjas | ADD | to MLB | 9:22 am, 5/18/21 |
| Alex Colome | Shaolin Schmeckles | ADD | to MLB | 9:36 pm, 5/17/21 |
| Jose Peraza | Nixon's Nasty Ninjas | ADD | to MLB | 1:08 pm, 5/17/21 |
| Jonathan Schoop | Nixon's Nasty Ninjas | ADD | to MLB | 1:07 pm, 5/17/21 |
| Gavin Sheets | The Bluth Company | ADD | to AAA | 1:07 pm, 5/17/21 |
| Ken Waldichuk | The Bluth Company | ADD | to A | 12:56 pm, 5/17/21 |
| Jordan Westburg | The Bluth Company | ADD | to AAA | 12:53 pm, 5/17/21 |
| Michael Baumann | The Bluth Company | ADD | to AAA | 11:37 am, 5/17/21 |
| Connor Joe | Purple Cobras | ADD | to MLB | 11:05 am, 5/17/21 |
| Brad Miller | The Red Barons | ADD | to MLB | 6:28 am, 5/17/21 |
| Jeremiah Jackson | The Red Barons | ADD | to AAA | 6:26 am, 5/17/21 |
| Collin McHugh | Undead Rabbits | ADD | to MLB | 12:27 pm, 5/16/21 |
| Kyle Zimmer | Undead Rabbits | ADD | to MLB | 12:26 pm, 5/16/21 |
| Albert Pujols | Undead Rabbits | ADD | to NA | 12:26 pm, 5/16/21 |
| Lorenzo Cain | Chinballs | ADD | to MLB | 9:17 am, 5/16/21 |
| Hansel Robles | Cowboys From Hell | ADD | to MLB | 8:54 am, 5/16/21 |
| Jimmy Nelson | Purple Cobras | ADD | to MLB | 7:05 am, 5/16/21 |
| Austin Adams | The Red Barons | ADD | to MLB | 4:07 pm, 5/15/21 |
| Miguel Rojas | Purple Cobras | ADD | to MLB | 6:49 am, 5/15/21 |
| Matt Beaty | Cowboys From Hell | ADD | to MLB | 8:48 pm, 5/14/21 |
| Mitch Moreland | Cowboys From Hell | ADD | to MLB | 8:47 pm, 5/14/21 |
| Freddy Galvis | Purple Cobras | ADD | to MLB | 7:18 pm, 5/14/21 |
| Erick Fedde | Cowboys From Hell | ADD | to MLB | 7:18 pm, 5/14/21 |
| Will Crowe | Cowboys From Hell | ADD | to MLB | 7:17 pm, 5/14/21 |
| Matt Frisbee | Purple Cobras | ADD | to AAA | 11:44 am, 5/14/21 |