Riley O'Brien career ERA
3.83Career Regular Season
Riley O'Brien has a career ERA of 3.83 over 5 regular seasons.
- Best season on file: 0.00 in 2022.
- Most recent: 4.08 in 2026.
Figures come from ESPN's box scores and were last read on September 22, 2026.
| GP: Games the player appeared in, however briefly. | W: Games in which this pitcher was credited with the win. | L: Games in which this pitcher was charged with the loss. | ERA: Earned runs allowed per nine innings pitched — lower is better. Under 3.00 is excellent. | IP: Innings pitched. The decimal counts outs, so 6.2 is six innings and two more outs. | K: Batters this pitcher struck out. | BB: Times the batter reached first base on four balls. | WHIP: Walks and hits allowed per inning pitched — lower is better. Around 1.00 is elite. | SV: Games finished by protecting a narrow lead to the last out. | ||
|---|---|---|---|---|---|---|---|---|---|---|
| 2021 |  CIN | 1 | 0 | 1 | 13.50 | 1.1 | 2 | 3 | 3.75 | 0 |
| 2022 |  SEA | 1 | 0 | 0 | 0.00 | 1.0 | 1 | 1 | 2.00 | 0 |
| 2024 |  STL | 8 | 0 | 0 | 11.25 | 8.0 | 11 | 8 | 2.63 | 0 |
| 2025 | STL | 42 | 3 | 1 | 2.06 | 48.0 | 45 | 22 | 1.15 | 6 |
| 2026 | STL | 66 | 3 | 9 | 4.08 | 64.0 | 64 | 29 | 1.28 | 38 |
What the columns mean: W · L · ERA · IP · K · BB · WHIP · SV
