Isaac Mattson (RP) - Pittsburgh Pirates MLB Stats 2025

Updated Oct 28, 2026 10:52 PM ET

Isaac Mattson

· RP · MLB · 4,772 views

31 yrs · 6' 2" · 205 lbs · 2017: Rd 19, Pk 565 (LAA) · Bats: Right / Throws: Right · Debut: 2021

FPPG (DK, 2025)

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ERA

2.61

W-L

4-3

51.2

2025 Season Stats

Isaac posted a 2.61 ERA over 51.2 innings pitched with a 4-3 record in 2025. He had struck out 49 batters and walked 21 and averaging 8.5 strikeouts per nine innings. His WHIP stood at 1.1, allowing 36 hits and 5 home runs.

Pitching Splits Pitching performance splits against left-handed and right-handed batters. 2025 Season - 198 TBF

Split	K%	K/9	BB%	wOBA	xFIP	HH%
vs LHB	19.6%	8.4	15.2%	0.447	5.74	39.4%
vs RHB	25.5%	8.6	4.7%	0.228	4.47	39.4%
Overall	22.7%	8.5	9.6%	0.329	4.93	39.4%

Pitching Splits — K% & BB% (2025) Strikeout and walk rates against left-handed batters, right-handed batters, and overall.

Pitching Splits — wOBA (2025) Weighted on-base average allowed against left-handed batters, right-handed batters, and overall. Lower is better for pitchers.

Pitching Splits — HH% (2025) Hard-hit rate allowed against left-handed batters, right-handed batters, and overall. Lower is better for pitchers.

Season Context Key season-level pitching metrics including games played, SIERA, and batted ball data. 2025 Season - 198 TBF

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SIERA

4.68

P/IP

16.5

TBF

198

HH%

39.4%

Barrel%

6.1%

CSW%

24.0%

CSW Prev

25.7%

GB%

29.9%

FB%

70.1%

Bullpen

4.02

RSB

0.16

Batted Ball Profile (2025) Ground ball vs fly ball tendency — higher GB% generally means fewer home runs allowed.

Traditional Stats Standard pitching stats: ERA, FIP, W/L, saves, holds, innings, and games started. 2025 Season

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Isaac Mattson MLB Stats 2025

Isaac Mattson is a RP for the Pittsburgh Pirates. For the 2026 season, Isaac had a 22.7% strikeout rate, a 4.93 xFIP, a 5.35 ERA, 38.2 innings pitched. View Isaac's 2026 stats, recent performance trends, and key statistical categories to evaluate fantasy value and make informed DFS lineup decisions.

Stats updated November 4, 2026.