 |
|
|
| League History Index | Players | Teams | Managers | Leagues | Leaderboards | Awards | Accomplishments |
| Player | From-To | W | L | Pct | ERA | G | GS | CG | SHO | SV | IP | H | ER | HR | BB | SO |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Mikey O'Brien | 2010-2012 | 1 | 3 | .250 | 3.08 | 34 | 1 | 0 | 0 | 1 | 61.1 | 63 | 21 | 2 | 16 | 13 |
| Riley O'Brien | 2022-2022 | 0 | 0 | .000 | 10.29 | 4 | 1 | 0 | 0 | 0 | 7.0 | 12 | 8 | 2 | 3 | 3 |
| Colin O'Connell | 2012-2012 | 0 | 0 | .000 | 5.68 | 5 | 0 | 0 | 0 | 0 | 6.1 | 6 | 4 | 0 | 2 | 6 |
| Darren O'Day | 2010-2022 | 40 | 33 | .548 | 3.78 | 638 | 0 | 0 | 0 | 92 | 671.0 | 570 | 282 | 82 | 281 | 851 |
| Billy O'Dell | 1954-1967 | 105 | 100 | .512 | 3.29 | 479 | 199 | 63 | 13 | 48 | 1817.0 | 1697 | 665 | 137 | 556 | 1133 |
| Eric O'Flaherty | 2007-2016 | 18 | 24 | .429 | 3.94 | 485 | 7 | 0 | 0 | 40 | 554.2 | 525 | 243 | 55 | 216 | 563 |
| Brian O'Grady | 2015-2020 | 4 | 9 | .308 | 6.67 | 17 | 17 | 0 | 0 | 0 | 120.0 | 142 | 89 | 17 | 87 | 74 |
| Ryan O'Hearn | 2015-2025 | 4 | 2 | .667 | 2.49 | 17 | 9 | 0 | 0 | 0 | 72.1 | 50 | 20 | 3 | 45 | 103 |
| Brian O'Keefe | 2015-2015 | 5 | 8 | .385 | 6.03 | 17 | 17 | 0 | 0 | 0 | 118.0 | 122 | 79 | 16 | 98 | 85 |
| Ryan O'Sullivan | 2012-2012 | 1 | 3 | .250 | 2.60 | 6 | 3 | 2 | 1 | 0 | 27.2 | 21 | 8 | 1 | 7 | 20 |
| Sean O'Sullivan | 2011-2011 | 0 | 1 | .000 | 12.00 | 3 | 3 | 0 | 0 | 0 | 12.0 | 25 | 16 | 2 | 7 | 5 |
| Trevor Oaks | 2015-2019 | 12 | 19 | .387 | 5.57 | 52 | 44 | 0 | 0 | 0 | 290.2 | 328 | 180 | 48 | 109 | 184 |
| Bailey Ober | 2022-2025 | 16 | 27 | .372 | 5.13 | 101 | 65 | 2 | 0 | 1 | 405.1 | 427 | 231 | 79 | 119 | 363 |
| Scott Oberg | 2019-2022 | 15 | 14 | .517 | 2.95 | 182 | 0 | 0 | 0 | 38 | 198.0 | 146 | 65 | 18 | 72 | 229 |
| Brett Oberholtzer | 2010-2016 | 13 | 9 | .591 | 3.89 | 46 | 24 | 1 | 0 | 0 | 178.0 | 162 | 77 | 14 | 51 | 160 |
| Josh Ockimey | 2015-2015 | 8 | 3 | .727 | 2.91 | 14 | 14 | 0 | 0 | 0 | 105.0 | 89 | 34 | 4 | 58 | 85 |
| Jake Odorizzi | 2012-2023 | 85 | 64 | .570 | 4.27 | 245 | 230 | 2 | 1 | 1 | 1305.1 | 1240 | 620 | 202 | 404 | 1160 |
| Alexi Ogando | 2012-2017 | 27 | 32 | .458 | 4.09 | 214 | 47 | 2 | 0 | 36 | 460.1 | 505 | 209 | 55 | 170 | 407 |
| Cesar Ogando | 2012-2012 | 3 | 5 | .375 | 1.66 | 9 | 9 | 3 | 1 | 0 | 70.1 | 45 | 13 | 2 | 9 | 27 |
| Nefi Ogando | 2017-2017 | 1 | 2 | .333 | 4.26 | 19 | 0 | 0 | 0 | 0 | 38.0 | 43 | 18 | 2 | 15 | 35 |
| Shinnosuke Ogasawara | 2025-2025 | 3 | 7 | .300 | 4.30 | 28 | 13 | 0 | 0 | 0 | 83.2 | 76 | 40 | 13 | 37 | 63 |
| Seung-hwan Oh | 2016-2019 | 5 | 11 | .312 | 4.03 | 207 | 0 | 0 | 0 | 9 | 234.1 | 218 | 105 | 39 | 68 | 267 |
| Ross Ohlendorf | 2009-2011 | 11 | 15 | .423 | 5.46 | 93 | 26 | 4 | 0 | 3 | 244.0 | 262 | 148 | 40 | 95 | 175 |
| Shohei Ohtani | 2018-2025 | 86 | 45 | .656 | 4.01 | 195 | 195 | 5 | 0 | 0 | 1126.0 | 961 | 502 | 162 | 433 | 1186 |
| Gabriel Ojeda | 2015-2015 | 3 | 6 | .333 | 5.75 | 17 | 14 | 0 | 0 | 0 | 92.1 | 91 | 59 | 12 | 79 | 79 |
| Steven Okert | 2016-2024 | 13 | 9 | .591 | 4.24 | 306 | 0 | 0 | 0 | 2 | 239.2 | 220 | 113 | 41 | 78 | 238 |
| Andy Oliver | 2010-2012 | 3 | 1 | .750 | 2.54 | 36 | 0 | 0 | 0 | 6 | 39.0 | 32 | 11 | 3 | 25 | 26 |
| Lester Oliveros | 2016-2016 | 7 | 6 | .538 | 4.84 | 70 | 1 | 0 | 0 | 4 | 109.2 | 103 | 59 | 14 | 50 | 98 |
| Alexis Olmeda | 2019-2019 | 0 | 0 | .000 | 0.00 | 1 | 0 | 0 | 0 | 0 | 2.0 | 1 | 0 | 0 | 1 | 0 |
| Edgar Olmos | 2010-2015 | 0 | 6 | .000 | 6.20 | 94 | 1 | 0 | 0 | 2 | 97.1 | 98 | 67 | 7 | 57 | 55 |
| Player | From-To | W | L | Pct | ERA | G | GS | CG | SHO | SV | IP | H | ER | HR | BB | SO |
| Reese Olson | 2024-2025 | 25 | 15 | .625 | 4.25 | 75 | 60 | 1 | 0 | 2 | 360.1 | 365 | 170 | 49 | 114 | 311 |
| Tyler Olson | 2018-2019 | 4 | 1 | .800 | 4.86 | 77 | 1 | 0 | 0 | 4 | 66.2 | 66 | 36 | 9 | 25 | 65 |
| Logan Ondrusek | 2012-2016 | 6 | 8 | .429 | 3.69 | 132 | 0 | 0 | 0 | 3 | 134.0 | 124 | 55 | 16 | 60 | 128 |
| Magglio Ordonez Jr. | 2015-2015 | 6 | 9 | .400 | 7.03 | 20 | 20 | 0 | 0 | 0 | 134.1 | 159 | 105 | 18 | 112 | 58 |
| Oliver Ortega | 2024-2025 | 0 | 4 | .000 | 4.48 | 70 | 0 | 0 | 0 | 2 | 78.1 | 71 | 39 | 12 | 29 | 83 |
| Joseph Ortiz | 2010-2014 | 6 | 4 | .600 | 4.35 | 102 | 0 | 0 | 0 | 2 | 120.0 | 119 | 58 | 12 | 40 | 122 |
| Luis Ortiz | 2023-2025 | 10 | 8 | .556 | 5.13 | 42 | 27 | 0 | 0 | 0 | 156.0 | 160 | 89 | 29 | 57 | 139 |
| Luis Ortiz | 2015-2025 | 0 | 0 | .000 | 9.00 | 1 | 0 | 0 | 0 | 0 | 2.0 | 3 | 2 | 2 | 0 | 1 |
| Josh Osich | 2012-2019 | 9 | 2 | .818 | 2.96 | 69 | 8 | 2 | 2 | 4 | 124.2 | 88 | 41 | 13 | 34 | 92 |
| Jose Osuna | 2012-2020 | 0 | 0 | .000 | 27.00 | 2 | 0 | 0 | 0 | 0 | 3.0 | 6 | 9 | 1 | 7 | 1 |
| Dan Otero | 2010-2019 | 27 | 16 | .628 | 3.43 | 394 | 0 | 0 | 0 | 22 | 487.2 | 499 | 186 | 45 | 100 | 406 |
| Travis Ott | 2018-2020 | 4 | 1 | .800 | 4.55 | 46 | 0 | 0 | 0 | 0 | 63.1 | 59 | 32 | 7 | 44 | 65 |
| Adam Ottavino | 2010-2024 | 41 | 43 | .488 | 3.49 | 724 | 3 | 0 | 0 | 46 | 742.1 | 628 | 288 | 72 | 326 | 859 |
| Glenn Otto | 2022-2025 | 5 | 7 | .417 | 6.64 | 43 | 18 | 0 | 0 | 1 | 118.0 | 133 | 87 | 24 | 57 | 112 |
| Connor Overton | 2021-2023 | 1 | 2 | .333 | 4.85 | 18 | 10 | 0 | 0 | 0 | 59.1 | 54 | 32 | 6 | 23 | 38 |
| Dillon Overton | 2017-2017 | 3 | 4 | .429 | 3.69 | 12 | 12 | 1 | 0 | 0 | 75.2 | 72 | 31 | 12 | 18 | 63 |
| Johan Oviedo | 2022-2025 | 5 | 3 | .625 | 3.75 | 41 | 8 | 0 | 0 | 0 | 105.2 | 93 | 44 | 14 | 34 | 91 |
| Juan Oviedo | 2008-2014 | 19 | 15 | .559 | 4.23 | 251 | 2 | 0 | 0 | 18 | 297.2 | 306 | 140 | 46 | 109 | 318 |
| Henry Owens | 2012-2012 | 1 | 1 | .500 | 2.21 | 3 | 3 | 0 | 0 | 0 | 20.1 | 19 | 5 | 0 | 6 | 20 |
| Rudy Owens | 2010-2016 | 11 | 23 | .324 | 5.17 | 147 | 35 | 1 | 0 | 4 | 341.0 | 420 | 196 | 53 | 93 | 263 |
