Pitcher · 2025
Isaiah Campbell
- Age
- 28
- B/T
- R/R
- Height
- 6' 4"
- Weight
- 230 lb
- Number
- #49
- Born
- August 15, 1997 in Angra de Heroismo, Portugal
- MLB debut
- July 7, 2023
- Drafted
- 2019, round CB-B
- College
- Arkansas
- High school
- Olathe South
- dbWAR
- -.3 2 season(s)
- IP
- 7.2
- ERA
- 7.04
- FIP
- 4.83
- K/9
- 3.5
- FIP−
- 116 100 = avg
Isaiah Campbell is a relief pitcher for the Boston Red Sox. In 2025 he struck out 3 batters over 7.2 innings across 6 appearances, going 0-0. His ERA of 7.04 was 69.4% higher than the league average of 4.16. Stripping out defence, his 4.83 FIP suggests he pitched better than his ERA shows. He missed bats on 21.0% of swings (11.9% of every pitch he threw), walked 2.9% of the batters he faced and struck out 8.6%. His -0.0 dbWAR is built from that FIP rather than runs allowed, so it credits him for what he controls and not for the defence behind him.
League context
Percentile among qualified pitchers, 2025.
Platoon splits
How left- and right-handed hitters fare against him.
| Split | PA | AB | H | HR | BB | SO | AVG | OBP | SLG | wOBA | K% |
|---|---|---|---|---|---|---|---|---|---|---|---|
| vs LHB | 12 | 11 | 5 | 0 | 1 | 0 | .455 | .500 | .455 | .429 | 0.0% |
| vs RHB | 23 | 22 | 8 | 1 | 0 | 3 | .364 | .391 | .591 | .416 | 13.0% |
Pitch sequencing
What Isaiah Campbell throws in each count, and what he follows each pitch with. Select any cell for the breakdown.
Select a count to see exactly what Isaiah Campbell throws in it.
Pitch arsenal
What he throws, how hard, and how often it misses in 2025.
| Slider | 46 | 90.5 | 2,680 | 45.7% | 22.2% | |
| Four-Seam Fastball | 20 | 96.0 | 2,511 | 45.0% | 20.0% | |
| Sweeper | 19 | 84.9 | 2,797 | 57.9% | 15.4% | |
| Curveball | 13 | 83.8 | 2,908 | 38.5% | 33.3% | |
| Sinker | 11 | 94.7 | 2,531 | 36.4% | 16.7% |
Pitching
Standard and advanced, by season.
| Trend | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2025 | 6 | 0 | 7.2 | 0 | 0 | 0 | 13 | 6 | 3 | 1 | 7.04 | 4.83 | 1.83 | 3.5 | 1.2 | 169 | 116 | -0.0 | |
| 2024 | 8 | 0 | 6.2 | 0 | 1 | 0 | 14 | 12 | 6 | 2 | 16.20 | 8.12 | 2.40 | 8.1 | 2.7 | 397 | 199 | -0.3 |
Head to head
Put Isaiah Campbell beside up to three others.
wOBA uses linear weights measured from this season's own play-by-play rather than published constants, and wRC+ is park-adjusted against that same league. dbWAR is our own open implementation — not fWAR or bWAR — and the full derivation, including its simplifications, is on the methodology page.