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Isaac Mattson

Pitcher · Pittsburgh Pirates. 2025 season stats with ranks among qualified players.

Pitching, 2025

Isaac Mattson posted a 2.45 ERA and a 3.66 FIP with a 22.7% strikeout rate over 47.7 innings in 2025.

Stat	2025	Percentile
Innings pitched	47.7	–
Starts	0	–
ERA	2.45	–
FIP	3.66	–
xFIP	4.95	–
Strikeout %	22.7%	–
Walk %	9.6%	–
K-BB%	13.1%	–
Home runs per 9	0.76	–
Whiff %	20.0%	–
Fastball velocity	93.9	–

Not enough innings in 2025 to compare.

Recent seasons

Season	IP	ERA	FIP	K%	BB%
2026	38.7	5.35	3.72	20.4%	10.2%
2025	47.7	2.45	3.66	22.7%	9.6%
2024	5.3	5.06	4.29	26.1%	21.7%

Pittsburgh Pirates teammates

Bryan Reynolds
Brandon Lowe
Nick Gonzales
Jake Mangum
Ryan O'Hearn
Spencer Horwitz
Oneil Cruz
Jared Triolo

About these numbers

Season totals and rates from every regular-season game. wRC+ is runs created adjusted for park and league (100 is average); FIP and xFIP estimate a pitcher's run prevention from strikeouts, walks and home runs; K-BB% is strikeout rate minus walk rate.

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