| Most Unearned Runs Allowed | |||||||
|---|---|---|---|---|---|---|---|
| Player | Team | Year | Age | IP | R | ER | UER |
| Jackie Varela | LBC | 1982 | 32 | 246.1 | 108 | 11 | 97 |
| LeRoy Hardy | SA,LV | 1978 | 33 | 73.1 | 76 | 37 | 39 |
| Mark Bobovnik | YS9,VAN | 1991 | 37 | 170.1 | 111 | 77 | 34 |
| Timo Dooley | OMA | 2054 | 34 | 206.1 | 128 | 95 | 33 |
| Nathaniel Davis | RCK | 2054 | 30 | 161.2 | 98 | 67 | 31 |
| Stephen Clulow, Jr. | BRK | 2054 | 19 | 139.2 | 134 | 104 | 30 |
| Cornelius Lattimore | LBC | 1978 | 37 | 242.0 | 108 | 80 | 28 |
| Stefan Barkley | YS9 | 1987 | 33 | 99.2 | 79 | 51 | 28 |
| Pete Redfern | SA | 1991 | 35 | 199.0 | 108 | 80 | 28 |
| Robert Walton | MAD | 1995 | 22 | 227.0 | 126 | 98 | 28 |
| Ron Vivero | YS9 | 1981 | 36 | 163.2 | 99 | 73 | 26 |
| Adrian Linares | CLG | 1982 | 31 | 190.0 | 115 | 89 | 26 |
| Gordon Graves | SEA | 2040 | 33 | 186.1 | 147 | 121 | 26 |
| Gary Owens | EDM | 2054 | 25 | 181.2 | 104 | 78 | 26 |
| Bill Swaggerty | SAC | 1986 | 29 | 212.1 | 140 | 115 | 25 |
| Cletus McGriff | CLG | 2005 | 28 | 224.0 | 127 | 102 | 25 |
| Sam Morton | SFB | 1988 | 27 | 185.0 | 112 | 87 | 25 |
| Rodger van der Knaap | EDM | 2032 | 30 | 199.1 | 136 | 111 | 25 |
| Fernando Pacheco | IND | 2031 | 24 | 217.2 | 116 | 91 | 25 |
| José MartÃnez | VAL | 2039 | 25 | 170.2 | 111 | 86 | 25 |