Aroldis Chapman had the lowest ERA by a relief pitcher in starts with 20+ games pitched in 2025, with an ERA of 1.17.
| NAME | ERA | G | GS | SEASON | TM | W | L | W% | SO | CG | SHO | SV | IP | H | ER | R | HR | BB | HBP | GF | IBB | TBF | WP | K/9 | BB/9 | K/BB | HR/9 | K% | BB% | WHIP | BABIP | RA | H/9 | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 |  | A. Chapman | 1.17 | 67 | 0 | 2025 |  BOS | 5 | 3 | .625 | 85 | 0 | 0 | 32 | 61.1 | 28 | 8 | 9 | 3 | 15 | 0 | 43 | 0 | 228 | 6 | 12.47 | 2.20 | 5.67 | 0.44 | 37.3 | 6.6 | 0.70 | .200 | 1.32 | 4.11 |
| 2 |  | A. Saalfrank | 1.24 | 28 | 0 | 2025 |  AZ | 2 | 1 | .667 | 19 | 0 | 0 | 3 | 29.0 | 19 | 4 | 5 | 1 | 10 | 0 | 10 | 1 | 113 | 2 | 5.90 | 3.10 | 1.90 | 0.31 | 16.8 | 8.8 | 1.00 | .217 | 1.55 | 5.90 |
| 3 | | E. Miller | 1.50 | 36 | 0 | 2025 |  SFG | 4 | 1 | .800 | 22 | 0 | 0 | 0 | 30.0 | 24 | 5 | 5 | 0 | 20 | 3 | 2 | 4 | 128 | 1 | 6.60 | 6.00 | 1.10 | 0.00 | 17.2 | 15.6 | 1.47 | .289 | 1.50 | 7.20 |
| 4 | | C. Winn | 1.51 | 33 | 0 | 2025 |  TEX | 0 | 1 | .000 | 35 | 0 | 0 | 0 | 41.2 | 23 | 7 | 8 | 3 | 17 | 4 | 10 | 2 | 162 | 1 | 7.56 | 3.67 | 2.06 | 0.65 | 21.6 | 10.5 | 0.96 | .194 | 1.73 | 4.97 |
| 5 |  | E. Díaz | 1.63 | 62 | 0 | 2025 |  NYM | 6 | 3 | .667 | 98 | 0 | 0 | 28 | 66.1 | 37 | 12 | 14 | 4 | 21 | 8 | 48 | 0 | 258 | 7 | 13.30 | 2.85 | 4.67 | 0.54 | 38.0 | 8.1 | 0.87 | .260 | 1.90 | 5.02 |
| 6 | | A. Uribe | 1.67 | 75 | 0 | 2025 |  MIL | 3 | 2 | .600 | 90 | 0 | 0 | 7 | 75.1 | 51 | 14 | 18 | 4 | 27 | 6 | 15 | 2 | 298 | 5 | 10.75 | 3.23 | 3.33 | 0.48 | 30.2 | 9.1 | 1.04 | .275 | 2.15 | 6.09 |
| 7 | | K. Strowd | 1.71 | 25 | 0 | 2025 |  BAL | 0 | 1 | .000 | 24 | 0 | 0 | 0 | 26.1 | 16 | 5 | 6 | 1 | 13 | 1 | 6 | 0 | 105 | 2 | 8.20 | 4.44 | 1.85 | 0.34 | 22.9 | 12.4 | 1.10 | .227 | 2.05 | 5.47 |
| 8 |  | A. Muñoz | 1.73 | 64 | 0 | 2025 |  SEA | 3 | 3 | .500 | 83 | 0 | 0 | 38 | 62.1 | 36 | 12 | 18 | 2 | 28 | 4 | 47 | 3 | 254 | 7 | 11.98 | 4.04 | 2.96 | 0.29 | 32.7 | 11.0 | 1.03 | .248 | 2.60 | 5.20 |
| 9 | | R. Rodríguez | 1.78 | 50 | 0 | 2025 | SFG | 3 | 5 | .375 | 67 | 0 | 0 | 4 | 50.2 | 34 | 10 | 12 | 4 | 11 | 4 | 15 | 0 | 198 | 2 | 11.90 | 1.95 | 6.09 | 0.71 | 33.8 | 5.6 | 0.89 | .268 | 2.13 | 6.04 |
| 10 | | E. Sabrowski | 1.84 | 33 | 0 | 2025 |  CLE | 0 | 1 | .000 | 42 | 0 | 0 | 0 | 29.1 | 14 | 6 | 8 | 2 | 21 | 3 | 3 | 0 | 121 | 0 | 12.89 | 6.44 | 2.00 | 0.61 | 34.7 | 17.4 | 1.19 | .226 | 2.45 | 4.30 |
| 11 | | B. Fisher | 1.85 | 51 | 0 | 2025 |  TOR | 7 | 0 | 1.000 | 61 | 0 | 0 | 0 | 48.2 | 28 | 10 | 10 | 2 | 18 | 3 | 12 | 1 | 193 | 0 | 11.28 | 3.33 | 3.39 | 0.37 | 31.6 | 9.3 | 0.95 | .239 | 1.85 | 5.18 |
| 12 | | J. Adam | 1.93 | 65 | 0 | 2025 |  SDP | 8 | 4 | .667 | 70 | 0 | 0 | 0 | 65.1 | 50 | 14 | 18 | 4 | 25 | 3 | 4 | 3 | 270 | 3 | 9.64 | 3.44 | 2.80 | 0.55 | 25.9 | 9.3 | 1.15 | .274 | 2.48 | 6.89 |
| 13 | | M. Svanson | 1.94 | 39 | 0 | 2025 |  STL | 4 | 0 | 1.000 | 68 | 0 | 0 | 0 | 60.1 | 33 | 13 | 14 | 3 | 20 | 4 | 10 | 0 | 234 | 1 | 10.14 | 2.98 | 3.40 | 0.45 | 29.1 | 8.5 | 0.88 | .216 | 2.09 | 4.92 |
| 14 | | D. Pomeranz | 1.94 | 53 | 0 | 2025 |  CHC | 2 | 2 | .500 | 53 | 0 | 0 | 1 | 46.1 | 36 | 10 | 12 | 5 | 13 | 5 | 11 | 1 | 190 | 1 | 10.29 | 2.53 | 4.08 | 0.97 | 27.9 | 6.8 | 1.06 | .272 | 2.33 | 6.99 |
| 15 | | T. Rogers | 1.98 | 81 | 0 | 2025 | TOT | 4 | 6 | .400 | 48 | 0 | 0 | 0 | 77.1 | 66 | 17 | 20 | 4 | 7 | 1 | 13 | 0 | 299 | 0 | 5.59 | 0.81 | 6.86 | 0.47 | 16.1 | 2.3 | 0.94 | .259 | 2.33 | 7.68 |
| 16 | | T. Nance | 1.99 | 30 | 0 | 2025 | TOR | 2 | 0 | 1.000 | 32 | 0 | 0 | 0 | 31.2 | 25 | 7 | 11 | 0 | 7 | 1 | 9 | 0 | 126 | 1 | 9.09 | 1.99 | 4.57 | 0.00 | 25.4 | 5.6 | 1.01 | .291 | 3.13 | 7.11 |
| 17 | | M. Vasil | 2.00 | 44 | 0 | 2025 |  CWS | 5 | 3 | .625 | 71 | 0 | 0 | 4 | 90.0 | 60 | 20 | 24 | 5 | 46 | 6 | 17 | 5 | 371 | 4 | 7.10 | 4.60 | 1.54 | 0.50 | 19.1 | 12.4 | 1.18 | .226 | 2.40 | 6.00 |
| 18 | | N. Enright | 2.03 | 27 | 0 | 2025 | CLE | 2 | 1 | .667 | 30 | 0 | 0 | 1 | 31.0 | 24 | 7 | 8 | 3 | 12 | 2 | 8 | 0 | 127 | 0 | 8.71 | 3.48 | 2.50 | 0.87 | 23.6 | 9.4 | 1.16 | .263 | 2.32 | 6.97 |
| 19 |  | J. Hader | 2.05 | 48 | 0 | 2025 |  HOU | 6 | 2 | .750 | 76 | 0 | 0 | 28 | 52.2 | 29 | 12 | 16 | 8 | 16 | 2 | 41 | 1 | 206 | 2 | 12.99 | 2.73 | 4.75 | 1.37 | 36.9 | 7.8 | 0.85 | .202 | 2.73 | 4.96 |
| 20 | | J. Duran | 2.06 | 72 | 0 | 2025 | TOT | 7 | 6 | .538 | 80 | 0 | 0 | 32 | 70.0 | 58 | 16 | 19 | 3 | 19 | 3 | 55 | 4 | 287 | 3 | 10.29 | 2.44 | 4.21 | 0.39 | 27.9 | 6.6 | 1.10 | .302 | 2.44 | 7.46 |
| 21 | | R. O'Brien | 2.06 | 42 | 0 | 2025 | STL | 3 | 1 | .750 | 45 | 0 | 0 | 6 | 48.0 | 33 | 11 | 13 | 2 | 22 | 7 | 15 | 2 | 199 | 3 | 8.44 | 4.13 | 2.05 | 0.38 | 22.6 | 11.1 | 1.15 | .252 | 2.44 | 6.19 |
| 22 | | J. Romero | 2.07 | 65 | 0 | 2025 | STL | 4 | 6 | .400 | 55 | 0 | 0 | 8 | 61.0 | 47 | 14 | 21 | 2 | 29 | 2 | 16 | 5 | 255 | 2 | 8.11 | 4.28 | 1.90 | 0.30 | 21.6 | 11.4 | 1.25 | .269 | 3.10 | 6.93 |
| 23 | | A. Morejon | 2.08 | 75 | 0 | 2025 | SDP | 13 | 6 | .684 | 70 | 0 | 0 | 3 | 73.2 | 49 | 17 | 23 | 2 | 17 | 0 | 9 | 3 | 286 | 2 | 8.55 | 2.08 | 4.12 | 0.24 | 24.5 | 5.9 | 0.90 | .239 | 2.81 | 5.99 |
| 24 | | M. Rodríguez | 2.08 | 31 | 0 | 2025 |  TBR | 1 | 2 | .333 | 25 | 0 | 0 | 0 | 30.1 | 26 | 7 | 9 | 2 | 6 | 1 | 4 | 0 | 121 | 1 | 7.42 | 1.78 | 4.17 | 0.59 | 20.7 | 5.0 | 1.05 | .276 | 2.67 | 7.71 |
| 25 | | B. Keller | 2.10 | 67 | 0 | 2025 | CHC | 4 | 2 | .667 | 73 | 0 | 0 | 3 | 68.2 | 45 | 16 | 18 | 4 | 22 | 6 | 12 | 0 | 273 | 1 | 9.57 | 2.88 | 3.32 | 0.52 | 26.7 | 8.1 | 0.98 | .244 | 2.36 | 5.90 |
StatMuse has game-level data for games pitched going back to the 1908 season.
Some of the information used here was obtained free of charge from Retrosheet.
More Red Sox Stats
Team Batting Leaders 
HR
25
Story
RBI
96
Story
AVG
.305
Gonzalez
Team Pitching Leaders 
W
18
Crochet
K
255
Crochet
ERA
2.59
Crochet
Team Rankings
HR
186
15th
R
786
7th
SO
1,361
16th
ERA
3.70
5th
Yankees
CIN
Phillies
Dodgers
Tigers
ATL
WSH
ATH
KCR
LAA
