| Player | POS | Team | NUM | Height | Weight | DOB |
|---|---|---|---|---|---|---|
| Jackson, Alex | C | MIA | 23 | 6'2" | 215 lbs | Dec 25, 1995 |
| Jackson, Luke | RP | ATL | 77 | 6'2" | 210 lbs | Aug 24, 1991 |
| Jankowski, Travis | RF | PHI | 9 | 6'2" | 190 lbs | Jun 15, 1991 |
| Jansen, Danny | C | TOR | 9 | 6'2" | 225 lbs | Apr 15, 1995 |
| Jansen, Kenley | RP | LAD | 74 | 6'5" | 265 lbs | Sep 30, 1987 |
| Javier, Cristian | RP | HOU | 53 | 6'1" | 213 lbs | Mar 26, 1997 |
| Jax, Griffin | RP | MIN | 83 | 6'2" | 195 lbs | Nov 22, 1994 |
| Jefferies, Daulton | RP | OAK | 66 | 6'0" | 182 lbs | Aug 2, 1995 |
| Jeffers, Ryan | C | MIN | 27 | 6'4" | 235 lbs | Jun 3, 1997 |
| Jimenez, Eloy | LF | CHW | 74 | 6'4" | 235 lbs | Nov 27, 1996 |
| Jimenez, Joe | RP | DET | 77 | 6'3" | 272 lbs | Jan 17, 1995 |
| Joe, Connor | RF | COL | 9 | 6'0" | 205 lbs | Aug 16, 1992 |
| Johnson, DJ | RP | TB | 54 | 6'4" | 230 lbs | Aug 30, 1989 |
| Johnson, Pierce | RP | SD | 36 | 6'2" | 202 lbs | May 10, 1991 |
| Jones, Damon | RP | PHI | 68 | 6'5" | 233 lbs | Sep 30, 1994 |
| Jones, Jahmai | 2B | BAL | 37 | 6'0" | 210 lbs | Aug 4, 1997 |
| Joyce, Matt | LF | PHI | 7 | 6'2" | 194 lbs | Aug 3, 1984 |
| Judge, Aaron | RF | NYY | 99 | 6'7" | 282 lbs | Apr 26, 1992 |
| Junis, Jakob | RP | KC | 24 | 6'3" | 220 lbs | Sep 16, 1992 |
| Junk, Janson | RP | LAA | 66 | 6'1" | 177 lbs | Jan 15, 1996 |
