O

Bob O’Brien
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1970 | CIN | 7.31 | 1 | 1 | 0 | 3 | 3 | 0 | 0 | 16.0 | 21 | 14 | 13 | 4 | 8 | 1 | 1.56 |
| Career | 7.31 | 1 | 1 | 0 | 3 | 3 | 0 | 0 | 16.0 | 21 | 14 | 13 | 4 | 8 | 1 | 1.56 | |

Billy O’Dell
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1954 | CLE | 3.24 | 1 | 0 | 0 | 13 | 0 | 0 | 0 | 16.2 | 13 | 6 | 6 | 2 | 5 | 1 | 0.93 |
| 1956 | CLE | 3.23 | 10 | 2 | 2 | 71 | 0 | 0 | 0 | 78.0 | 75 | 34 | 28 | 28 | 59 | 10 | 1.32 |
| 1958 | CLE | 2.71 | 11 | 7 | 2 | 31 | 25 | 4 | 1 | 182.2 | 161 | 68 | 55 | 40 | 133 | 22 | 1.10 |
| 1960 | CLE | 3.49 | 11 | 9 | 0 | 31 | 31 | 4 | 3 | 201.0 | 195 | 89 | 78 | 83 | 115 | 17 | 1.38 |
| 1962 | CLE | 3.47 | 13 | 9 | 0 | 31 | 31 | 4 | 1 | 207.2 | 198 | 88 | 80 | 69 | 122 | 18 | 1.29 |
| 1964 | CLE | 3.16 | 4 | 5 | 7 | 38 | 1 | 0 | 0 | 57.0 | 43 | 22 | 20 | 24 | 54 | 6 | 1.18 |
| 1966 | BOS | 4.10 | 4 | 4 | 0 | 17 | 11 | 3 | 1 | 79.0 | 78 | 38 | 36 | 35 | 41 | 6 | 1.43 |
| Career | 3.32 | 54 | 36 | 11 | 232 | 99 | 15 | 6 | 822.0 | 763 | 345 | 303 | 281 | 529 | 80 | 1.27 | |

George O’Donnell
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1954 | BRK | 3.42 | 1 | 0 | 0 | 33 | 0 | 0 | 0 | 52.2 | 55 | 23 | 20 | 17 | 4 | 6 | 1.38 |
| Career | 3.42 | 1 | 0 | 0 | 33 | 0 | 0 | 0 | 52.2 | 55 | 23 | 20 | 17 | 4 | 6 | 1.37 | |

John O’Donoghue
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1962 | HOU | 24.55 | 0 | 0 | 0 | 4 | 0 | 0 | 0 | 3.2 | 12 | 10 | 10 | 5 | 0 | 1 | 5.31 |
| 1964 | HOU | 4.14 | 10 | 18 | 0 | 36 | 36 | 4 | 2 | 210.2 | 212 | 109 | 97 | 63 | 112 | 21 | 1.31 |
| 1966 | HOU | 3.77 | 8 | 9 | 0 | 23 | 23 | 2 | 2 | 150.1 | 162 | 70 | 63 | 23 | 101 | 9 | 1.23 |
| 1968 | HOU | 3.45 | 4 | 2 | 1 | 50 | 0 | 0 | 0 | 60.0 | 46 | 26 | 23 | 23 | 41 | 5 | 1.15 |
| 1970 | HOU | 5.05 | 2 | 6 | 2 | 34 | 0 | 0 | 0 | 35.2 | 36 | 22 | 20 | 19 | 21 | 5 | 1.56 |
| Career | 4.16 | 24 | 35 | 3 | 147 | 59 | 6 | 4 | 460.1 | 468 | 237 | 213 | 133 | 275 | 41 | 1.31 | |

Jim O’Toole
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1958 | DET | 4.78 | 1 | 5 | 0 | 18 | 8 | 0 | 0 | 58.1 | 74 | 32 | 31 | 28 | 26 | 7 | 1.76 |
| 1960 | DET | 3.31 | 13 | 8 | 0 | 36 | 36 | 4 | 1 | 239.0 | 207 | 89 | 88 | 91 | 130 | 23 | 1.25 |
| 1962 | DET | 4.16 | 8 | 11 | 0 | 28 | 28 | 0 | 0 | 155.2 | 170 | 87 | 72 | 63 | 73 | 17 | 1.50 |
| 1964 | DET | 2.52 | 17 | 7 | 0 | 31 | 31 | 8 | 2 | 225.0 | 187 | 80 | 63 | 42 | 186 | 16 | 1.02 |
| 1966 | DET | 3.22 | 11 | 6 | 0 | 21 | 20 | 2 | 0 | 131.1 | 115 | 56 | 47 | 59 | 78 | 15 | 1.33 |
| Career | 3.35 | 50 | 37 | 0 | 134 | 123 | 14 | 3 | 809.1 | 753 | 344 | 301 | 283 | 493 | 78 | 1.28 | |

Blue Moon Odom
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1964 | NYM | 7.29 | 0 | 0 | 0 | 17 | 0 | 0 | 0 | 21.0 | 37 | 20 | 17 | 10 | 9 | 7 | 2.24 |
| 1966 | NYM | 2.12 | 4 | 1 | 0 | 61 | 0 | 0 | 0 | 101.2 | 77 | 29 | 24 | 43 | 48 | 3 | 1.18 |
| 1968 | NYM | 2.93 | 11 | 8 | 0 | 29 | 29 | 4 | 1 | 178.0 | 149 | 66 | 58 | 66 | 109 | 8 | 1.21 |
| 1970 | NYM | 4.83 | 10 | 9 | 0 | 33 | 33 | 4 | 2 | 188.1 | 156 | 117 | 101 | 148 | 117 | 20 | 1.61 |
| Career | 3.68 | 25 | 18 | 0 | 140 | 62 | 8 | 3 | 489.0 | 419 | 232 | 200 | 267 | 283 | 38 | 1.40 | |

Chi-Chi Olivo
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1964 | CAA | 3.89 | 1 | 2 | 1 | 30 | 1 | 0 | 0 | 41.2 | 42 | 24 | 18 | 19 | 47 | 7 | 1.48 |
| 1966 | CAA | 0.64 | 2 | 0 | 0 | 23 | 0 | 0 | 0 | 42.1 | 27 | 9 | 3 | 14 | 27 | 0 | 0.97 |
| Career | 2.25 | 3 | 2 | 1 | 53 | 1 | 0 | 0 | 84.0 | 69 | 33 | 21 | 33 | 74 | 7 | 1.21 | |

Diomedes Olivo
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1960 | MIN | 1.69 | 1 | 1 | 0 | 9 | 0 | 0 | 0 | 10.2 | 9 | 2 | 2 | 9 | 1 | 0 | 1.77 |
| 1962 | MIN | 4.22 | 7 | 7 | 4 | 64 | 5 | 0 | 0 | 96.0 | 105 | 49 | 45 | 24 | 63 | 12 | 1.34 |
| Career | 3.97 | 8 | 8 | 4 | 73 | 5 | 0 | 0 | 106.2 | 114 | 51 | 47 | 33 | 64 | 12 | 1.38 | |

Jim Ollom
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1966 | ATL | 10.80 | 0 | 1 | 1 | 15 | 0 | 0 | 0 | 11.2 | 22 | 14 | 14 | 3 | 5 | 3 | 2.23 |
| Career | 10.80 | 0 | 1 | 1 | 15 | 0 | 0 | 0 | 11.2 | 22 | 14 | 14 | 3 | 5 | 3 | 2.14 | |

Phil Ortega
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1960 | PHI | 6.00 | 0 | 1 | 0 | 4 | 0 | 0 | 0 | 6.0 | 7 | 4 | 4 | 0 | 8 | 3 | 1.17 |
| 1962 | PHI | 7.59 | 0 | 3 | 1 | 34 | 2 | 0 | 0 | 53.1 | 81 | 49 | 45 | 37 | 34 | 13 | 2.22 |
| 1964 | PHI | 2.96 | 2 | 6 | 0 | 32 | 17 | 2 | 1 | 130.2 | 128 | 58 | 43 | 42 | 81 | 11 | 1.31 |
| 1966 | PHI | 3.01 | 12 | 10 | 0 | 33 | 33 | 5 | 4 | 212.1 | 202 | 82 | 71 | 44 | 101 | 16 | 1.16 |
| 1968 | SEP | 5.66 | 4 | 18 | 0 | 32 | 27 | 1 | 0 | 146.1 | 180 | 108 | 92 | 69 | 54 | 21 | 1.70 |
| Career | 4.18 | 18 | 38 | 1 | 135 | 79 | 8 | 5 | 548.2 | 598 | 301 | 255 | 192 | 278 | 64 | 1.44 | |

Dan Osinski
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1962 | CIN | 4.99 | 7 | 2 | 2 | 36 | 4 | 0 | 0 | 74.0 | 78 | 45 | 41 | 30 | 34 | 17 | 1.46 |
| 1964 | CIN | 3.60 | 6 | 3 | 0 | 35 | 8 | 0 | 0 | 90.0 | 92 | 37 | 36 | 29 | 61 | 4 | 1.34 |
| 1966 | CIN | 2.87 | 6 | 5 | 5 | 47 | 0 | 0 | 0 | 78.1 | 77 | 27 | 25 | 14 | 38 | 7 | 1.17 |
| 1968 | CIN | 3.82 | 3 | 2 | 6 | 55 | 0 | 0 | 0 | 63.2 | 54 | 29 | 27 | 27 | 38 | 4 | 1.28 |
| Career | 3.79 | 22 | 12 | 13 | 173 | 12 | 0 | 0 | 306.0 | 301 | 138 | 129 | 100 | 171 | 32 | 1.31 | |

Claude Osteen
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1956 | BAL | 15.19 | 0 | 0 | 0 | 6 | 0 | 0 | 0 | 5.1 | 9 | 9 | 9 | 8 | 0 | 0 | 3.33 |
| 1958 | BAL | 13.11 | 0 | 0 | 0 | 7 | 0 | 0 | 0 | 11.2 | 16 | 17 | 17 | 10 | 7 | 3 | 2.32 |
| 1960 | BAL | 7.12 | 2 | 5 | 1 | 53 | 1 | 0 | 0 | 54.1 | 66 | 46 | 43 | 41 | 5 | 6 | 1.98 |
| 1962 | BAL | 5.27 | 5 | 11 | 0 | 52 | 14 | 0 | 0 | 114.1 | 134 | 73 | 67 | 51 | 48 | 12 | 1.62 |
| 1964 | BAL | 3.56 | 12 | 11 | 0 | 32 | 32 | 7 | 0 | 217.2 | 194 | 92 | 86 | 72 | 150 | 26 | 1.23 |
| 1966 | BAL | 3.63 | 9 | 16 | 0 | 32 | 32 | 2 | 0 | 208.1 | 200 | 98 | 84 | 64 | 117 | 10 | 1.27 |
| 1968 | BAL | 2.87 | 18 | 6 | 0 | 32 | 32 | 7 | 4 | 210.1 | 194 | 72 | 67 | 40 | 129 | 13 | 1.11 |
| 1970 | BAL | 4.40 | 5 | 7 | 0 | 24 | 24 | 1 | 0 | 149.1 | 164 | 79 | 73 | 38 | 79 | 18 | 1.36 |
| Career | 4.13 | 51 | 56 | 1 | 238 | 135 | 17 | 4 | 971.1 | 977 | 486 | 446 | 324 | 535 | 88 | 1.34 | |

Fritz Ostermueller
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1946 | DET | 4.98 | 9 | 12 | 0 | 30 | 30 | 7 | 0 | 173.2 | 217 | 112 | 96 | 56 | 49 | 10 | 1.58 |
| 1948 | DET | 4.13 | 5 | 5 | 11 | 60 | 0 | 0 | 0 | 65.1 | 73 | 32 | 30 | 25 | 22 | 7 | 1.51 |
| Career | 4.74 | 14 | 17 | 11 | 90 | 30 | 7 | 0 | 239.0 | 290 | 144 | 126 | 81 | 71 | 17 | 1.55 | |

Joe Ostrowski
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1948 | BRK | 5.91 | 4 | 4 | 0 | 23 | 12 | 0 | 0 | 77.2 | 113 | 54 | 51 | 16 | 17 | 11 | 1.67 |
| 1950 | BRK | 5.01 | 5 | 2 | 0 | 46 | 0 | 0 | 0 | 41.1 | 61 | 23 | 23 | 10 | 11 | 5 | 1.73 |
| 1952 | BRK | 9.10 | 2 | 4 | 2 | 19 | 0 | 0 | 0 | 29.2 | 53 | 33 | 30 | 18 | 9 | 10 | 2.43 |
| Career | 6.30 | 11 | 10 | 2 | 88 | 12 | 0 | 0 | 148.2 | 227 | 110 | 104 | 44 | 37 | 26 | 1.82 | |

Stubby Overmire
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1946 | PHA | 3.06 | 5 | 4 | 7 | 71 | 8 | 1 | 0 | 144.0 | 156 | 57 | 49 | 51 | 33 | 7 | 1.44 |
| 1948 | PHA | 6.23 | 0 | 0 | 0 | 3 | 0 | 0 | 0 | 4.1 | 5 | 3 | 3 | 2 | 0 | 0 | 1.71 |
| 1950 | PHA | 4.54 | 11 | 8 | 3 | 43 | 21 | 3 | 0 | 186.1 | 227 | 109 | 94 | 61 | 45 | 7 | 1.55 |
| 1952 | PHA | 4.78 | 1 | 1 | 1 | 35 | 0 | 0 | 0 | 43.1 | 51 | 25 | 23 | 8 | 19 | 10 | 1.37 |
| Career | 4.02 | 17 | 13 | 11 | 152 | 29 | 4 | 0 | 378.0 | 439 | 194 | 169 | 122 | 97 | 24 | 1.48 | |

Jim Owens
| Year | Team | ERA | W | L | SV | G | GS | CG | SHO | INN | H | R | ER | BB | SO | HR | Whip |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1956 | CIN | 8.10 | 0 | 1 | 1 | 21 | 0 | 0 | 0 | 26.2 | 45 | 29 | 24 | 18 | 16 | 3 | 2.41 |
| 1958 | CIN | 3.02 | 14 | 4 | 0 | 25 | 25 | 4 | 1 | 176.0 | 161 | 73 | 59 | 52 | 112 | 13 | 1.21 |
| 1960 | CAA | 5.26 | 3 | 9 | 2 | 42 | 18 | 0 | 0 | 119.2 | 143 | 85 | 70 | 43 | 45 | 15 | 1.56 |
| 1962 | CAA | 6.44 | 3 | 3 | 0 | 31 | 6 | 0 | 0 | 58.2 | 69 | 44 | 42 | 32 | 16 | 13 | 1.74 |
| 1964 | CAA | 3.94 | 6 | 9 | 1 | 29 | 21 | 1 | 1 | 139.1 | 156 | 66 | 61 | 34 | 126 | 7 | 1.37 |
| Career | 4.43 | 26 | 26 | 4 | 148 | 70 | 5 | 2 | 520.1 | 574 | 297 | 256 | 179 | 315 | 51 | 1.45 | |