Players · F · Pitcher · 2026 regular season

Jack Flaherty

Age: 31
B/T: R/R
Height: 6' 4"
Weight: 225 lb
Number: #9

Born: October 15, 1995 in Burbank, CA, United States
MLB debut: September 1, 2017
Drafted: 2014, round 1
High school: Harvard-Westlake
Salary, 2026: $10M

Compare with…vs Tarik Skubal vs MacKenzie Gore vs Casey Mize

dbWAR: 17.6
IP: 88.1
ERA: 4.48
FIP: 4.05
K/9: 10.5
FIP−: 97

Jack Flaherty is a starting pitcher for the Detroit Tigers. In 2026 he struck out 103 batters over 88.1 innings across 20 appearances, 19 of them starts, going 3-8. His ERA of 4.48 was 7.2% higher than the league average of 4.18 — 16th of 20 on his team, and 341st of 539 among MLB pitchers with 20+ innings. Stripping out defence, his 4.05 FIP suggests he pitched better than his ERA shows. He missed bats on 27.1% of swings (12.2% of every pitch he threw), walked 10.6% of the batters he faced and struck out 26.0%. His 1.1 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, 2026 regular season.

FIP4.05

K/910.5

WHIP1.39

WAR1.1

WAR by season

Pitching Regular season

Standard and advanced, by season. Regular-season games only — postseason games are listed separately below.


2026	DET	20	19	88.1	3	8	81	44	103	42	4.48	4.05	1.39	10.5	4.3	107	97	1.1
2025	DET	31	31	161.0	8	15	147	83	188	59	4.64	3.85	1.28	10.5	3.3	112	93	2.6
2024	DET/LAD	28	28	162.0	13	7	135	57	194	38	3.17	3.48	1.07	10.8	2.1	78	85	3.1
2023	STL/BAL	29	27	144.1	8	9	162	80	148	66	4.99	4.36	1.58	9.2	4.1	115	101	1.8
2022	STL	9	8	36.0	2	1	36	17	33	22	4.25	4.97	1.61	8.3	5.5	107	125	-0.0
2021	STL	17	15	78.1	9	2	57	28	85	26	3.22	4.22	1.06	9.8	3.0	75	99	0.9
2020	STL	9	9	40.1	4	3	33	22	49	16	4.91	4.11	1.21	10.9	3.6	110	92	0.7
2019	STL	33	33	196.1	11	8	135	60	231	55	2.75	3.46	0.97	10.6	2.5	61	77	4.5
2018	STL	28	28	151.0	8	9	108	56	182	59	3.34	3.86	1.11	10.8	3.5	80	93	2.2
2017	STL	6	5	21.1	0	2	23	15	20	10	6.33	5.27	1.55	8.4	4.2	145	121	-0.0

Batting Regular season

Standard and advanced, by season. Regular-season games only — postseason games are listed separately below.


2021	STL	11	26	2	1	3	0	5	7	.118	.304	.294	.176	.100	19.2%	26.9%	.282	-0.8	80	0.3
2019	STL	30	66	10	0	4	1	2	17	.185	.211	.241	.056	.263	3.0%	25.8%	.196	-7.1	14	0.3
2018	STL	26	52	7	0	0	0	2	20	.152	.188	.152	.000	.269	3.8%	38.5%	.158	-6.8	-11	0.1
2017	STL	4	6	0	0	0	0	0	2	.000	.000	.000	.000	.000	0.0%	33.3%	.000	-1.6	-126	-0.1

Separate from the regular season

Postseason Postseason

Wild Card through World Series. These games are counted on their own: none of them are in the regular-season tables, career totals, league context, leaderboards or dbWAR on this page.

Postseason pitching

Postseason Jack Flaherty's postseason pitching, by October and round. Not part of any regular-season figure on this page.
Season	Team	Round	G	GS	IP	W	L	H	ER	HR	BB	SO	ERA	WHIP	K/9
2025 Post	DET	Postseason total	3	2	10.0	0	1	7	4	1	8	12	3.60	1.50	10.8
		Wild Card	1	1	4.2	0	0	3	1	0	2	4	1.93	1.07	7.7
		ALDS	2	1	5.1	0	1	4	3	1	6	8	5.06	1.88	13.5
2024 Post	LAD	Postseason total	5	5	22.0	1	2	24	18	6	9	15	7.36	1.50	6.1
		NLDS	1	1	5.1	0	1	5	4	2	1	2	6.75	1.13	3.4
		NLCS	2	2	10.0	1	1	10	8	1	6	6	7.20	1.60	5.4
		World Series	2	2	6.2	0	0	9	6	3	2	7	8.10	1.65	9.4
2023 Post	BAL	ALDS	1	0	2.0	0	0	2	1	0	3	1	4.50	2.50	4.5
2020 Post	STL	Wild Card	1	1	6.0	0	1	6	1	0	2	8	1.50	1.33	12.0
2019 Post	STL	Postseason total	3	3	17.0	1	2	17	8	2	4	22	4.24	1.24	11.6
		NLDS	2	2	13.0	1	1	12	4	2	2	16	2.77	1.08	11.1
		NLCS	1	1	4.0	0	1	5	4	0	2	6	9.00	1.75	13.5
Career		Postseason total · 5 Octobers	13	11	57.0	2	6	56	32	9	26	58	5.05	1.44	9.2

Postseason batting

Postseason Jack Flaherty's postseason batting, by October and round. Not part of any regular-season figure on this page.
Season	Team	Round	G	PA	AB	R	RBI	BB	SO	AVG	OBP	SLG	OPS
2019 Post	STL	Postseason total	3	7	6	1	1	1	4	.000	.143	.000	.143
		NLDS	2	6	5	1	1	1	3	.000	.167	.000	.167
		NLCS	1	1	1	0	0	0	1	.000	.000	.000	.000

Box-score and rate statistics only. wOBA, wRC+, FIP and dbWAR are measured against a full league season, and a postseason is a few teams playing each other for a month, so they are not computed for October.

Platoon splits

How left- and right-handed hitters fare against him.

Season

Opponent batting by the side the hitter bats from, 2026. Counted from play-by-play, so totals can differ from the box-score season line by a plate appearance or two.
Split	PA	AB	H	HR	BB	SO	AVG	OBP	SLG	wOBA	K%
vs LHB	218	183	42	5	29	50	.230	.338	.388	.328	22.9%
vs RHB	178	158	39	6	13	53	.247	.320	.437	.330	29.8%

Pitch sequencing

What Jack Flaherty throws in each count, and what he follows each pitch with. Select any cell for the breakdown.

ShowBatter

Four-seamSliderKnuckle curveSinkerChangeup

Select a count to see exactly what Jack Flaherty throws in it.

Pitch arsenal

What he throws, how hard, how often it misses, and what hitters do with it.

Season


Four-Seam Fastball	49.2%	816	92.7	2,256	51.8%	21.2%	174	.218	.701
Slider	24.3%	403	85.0	2,439	43.9%	32.1%	91	.286	.857
Knuckle Curve	19.4%	322	78.1	2,401	44.1%	37.6%	60	.250	.762
Sinker	4.4%	73	90.9	2,061	27.4%	24.0%	12	—	—
Changeup	2.7%	44	85.5	1,818	20.5%	25.0%	4	—	—

Jack Flaherty's arsenal by usage. Velocity is average release speed in mph, spin in rpm, and whiff rate is misses per swing — the cleanest single measure of whether a pitch beats hitters. BAA and OPS are what hitters did against each pitch, credited to the one that ended the plate appearance, and are left blank under 15 at-bats.

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Similar players

Nearest 2026 seasons by command, run prevention and role, on rate statistics rather than totals.

MacKenzie GoreTEX

ERA: 4.58
FIP: 3.87
SO: 174
WAR: 2.6

Very close

Luis SeverinoATH

ERA: 4.16
FIP: 4.48
SO: 65
WAR: 0.7

Very close

Joey CantilloCLE

ERA: 3.62
FIP: 3.98
SO: 171
WAR: 2.3

Very close

Eury PérezMIA

ERA: 3.91
FIP: 4.07
SO: 170
WAR: 2.0

Very close

How these are computed

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.