Cooper Criswell

Active

Seattle Mariners · RP

Age 306' 6" · 200 lbsThrows Right

#571 Current

FBaseball Overview

Working out of the Seattle Mariners' bullpen, this 29-year-old right-hander offers modest value as a multi-inning reliever with occasional save opportunities. Through early 2026, he's posted a 3.52 ERA with a 1.17 WHIP across 30.2 innings while recording 23 strikeouts, showing improved command and efficiency compared to his limited 2025 sample. The primary appeal lies in his dual eligibility for wins and saves, though neither category projects as a major source of production given his reserve role and the depth of Seattle's bullpen. Fantasy managers should view him as a speculative depth piece rather than a core contributor, with upside only if he secures a more prominent role or earns consistent save chances.

MLB Pitching

Year	Team	G	GS	W	L	SV	ERA	WHIP	K	IP	BB
2021	Los Angeles Angels	1	1	0	1	0	20.25	4.50	0	1.1	0
2022	Tampa Bay Rays	1	1	0	0	0	2.70	0.90	4	3.1	1
2023	Tampa Bay Rays	10	0	1	1	0	5.73	1.55	27	33.0	11
2024	Boston Red Sox	26	18	6	5	0	4.08	1.35	73	99.1	31
2025	Boston Red Sox	7	1	1	0	1	3.57	1.58	9	17.2	5
2026	Seattle Mariners	37	0	4	2	1	3.32	1.40	31	40.2	16
Career	Totals	82	21	12	9	2	4.24	1.43	144	195.1	64

Source: MLB Stats API · Multi-team seasons show combined totals — click to expand

Minor League Pitching

Year	Team	G	GS	W	L	SV	ERA	WHIP	K	IP	BB
2019	Inland Empire 66ers	25	21	4	8	0	4.60	1.43	111	117.1	35
2021	2 teams▼	21	21	9	9	0	4.83	1.24	128	117.1	20
2022	3 teams▼	17	9	2	2	0	3.95	1.06	57	54.2	10
2023	Durham Bulls	23	17	4	4	2	3.93	1.30	80	84.2	23
2024	Worcester Red Sox	5	5	2	2	0	1.40	1.13	23	25.2	8
2025	Worcester Red Sox	16	14	4	2	0	3.70	1.34	68	65.2	28
2026	Tacoma Rainiers	3	0	2	0	0	10.13	1.13	3	2.2	1
Career	Totals	110	87	27	27	2	4.19	1.28	470	468	125

Source: MLB Stats API · Multi-team seasons show combined totals — click to expand

Last Week / Last Month

Current season · MLB only

7 games

G	GS	IP	W-L	SV	ERA	WHIP	K	BB
7	0	6.2	1-0	0	2.70	1.95	5	6

30 games

G	GS	IP	W-L	SV	ERA	WHIP	K	BB
30	0	30.2	4-2	0	3.82	1.50	23	13

Game Log2026 MLB

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Advanced Stats2026 season · via Baseball Savant

Click for year to year changes

FB Velo90.7 mph

Avg Spin2091 rpm

Whiff %20.7%

K %18.0%

BB %9.3%

Hard Hit %37.9%

Barrel %4.8%

xERA3.81

xBA Against0.253

xSLG Against0.362

BA Against0.272

SLG Against0.377

What These Stats Mean

FB Velo — Average fastball velocity. Harder throwers generate more swings and misses, setting up every other pitch in their arsenal. Velocity is the foundation of strikeout upside.

Avg Spin — Average spin rate across all pitches. Higher spin creates more movement and makes pitches harder to square up — elite spinners run better strikeout and batting average against numbers.

Whiff % — Swings-and-misses per swing. The most direct measure of a pitcher's ability to miss bats and the best leading indicator of strikeout rate.

K % — Strikeout rate per batter faced. The core fantasy pitching stat — high K% means reliable strikeout totals that hold up even in shorter starts.

BB % — Walk rate per batter faced. The primary control metric. High BB% tanks ERA and WHIP and keeps baserunners on constantly. Elite starters typically run below 7%.

Hard Hit % — Percentage of batted balls hit 95 mph or harder against. Low hard-hit% means weak contact, protecting both ERA and the defense behind the pitcher.

Barrel % — Percentage of batted balls barreled against. The most direct home run predictor — low barrel% pitchers rarely give up long balls.

xERA — Expected ERA based on contact quality allowed, removing the effect of sequencing, luck, and defense. Better predictor of future ERA than ERA itself.

xBA Against — Expected batting average opponents should hit based on contact quality. A gap between xBA and actual BA indicates unsustainable luck in either direction.

xSLG Against — Expected slugging allowed based on contact quality. High xSLG against predicts future extra-base damage; low xSLG means the pitcher is genuinely suppressing power.

BA Against — Actual batting average opponents are hitting — a key WHIP component. Check xBA to see if the number is sustainable.

SLG Against — Actual slugging allowed. Captures hits, doubles, triples, and home runs — lower means the pitcher is limiting the power damage he gives up.

GB% — Ground ball rate. High GB% pitchers generate double plays, limit home runs, and keep the ball in the park — great for protecting ERA and WHIP ratios.

FB% — Fly ball rate. High FB% pitchers give up more air contact — dangerous when combined with high exit velocity, less so when contact is soft.

Loading player data...

Year

Team

ERA

WHIP

2021

Los Angeles Angels

20.25

4.50

1.1

2022

Tampa Bay Rays

2.70

0.90

3.1

2023

Tampa Bay Rays

5.73

1.55

33.0

2024

Boston Red Sox

4.08

1.35

99.1

2025

Boston Red Sox

3.57

1.58

17.2

2026

Seattle Mariners

3.32

1.40

40.2

Career

Totals

4.24

1.43

144

195.1

Year

Team

ERA

WHIP

2019

Inland Empire 66ers

4.60

1.43

111

117.1

2021

2 teams▼

4.83

1.24

128

117.1

2022

3 teams▼

3.95

1.06

54.2

2023

Durham Bulls

3.93

1.30

84.2

2024

Worcester Red Sox

1.40

1.13

25.2

2025

Worcester Red Sox

3.70

1.34

65.2

2026

Tacoma Rainiers

10.13

1.13

2.2

Career

Totals

110

4.19

1.28

470

468

125

W-L

ERA

WHIP

6.2

1-0

2.70

1.95

W-L

ERA

WHIP

30.2

4-2

3.82

1.50