STL · P

Quinn Mathews

Age 26 B/T L/L 6′5″, 188 lb USA MLB debut 2026

40-man FV 45 · #10 in org

St. Louis’ roster as it stands #5 starter · 102 IP · 1.2 WAR in the role
Trade read Available at a price: STL 27% playoff odds; control through 2032.

Keystone Stuff 94 27th pct

2026 fWAR 0.8

Projected 2027 WAR 1.1 at 95 IP · 1.2 in his 2027 role

Pitching · 2026 percentiles

vs. MLB pitchers with 500+ pitches · 867 pitches

Keystone Stuff 94

Keystone Location 103

Keystone Pitching 97

Run value (xRV) +0.18

Strikeout % 21.8%

Walk % 9.5%

Whiff % 26.5%

Chase % 26.0%

Fastball velo 93.3

Extension 6.6 ft

49.1 IP3.83 ERA3.83 FIP 38° arm

Arsenal & Pitch Lab

Movement normalized to arm side · Keystone Stuff by pitch

LHP · arm angle 38° · how to read

Pitch	Use	Velo	IVB	HB	Stuff	Loc	Whiff	xRV/100
Four-seam39% use	39%	93.4	16.3	+5.1	100	98	24%	+0.15
Slider22% use	22%	84.8	1.3	−3.5	100	112	26%	+0.03
Changeup16% use	16%	83.0	4.4	+11.0	87	97	43%	−0.09
Curveball13% use	13%	75.8	−12.1	−9.9	99	93	21%	+0.45
Sinker10% use	10%	92.9	12.5	+10.8	81	111	17%	+0.76

No mix change or new pitch clears its bar. The arsenal is efficient for its shapes.

Most similar pitchers

Pitches like Mathews: same hand, shape, slot and mix

Similarity	Player	Stuff	’26 WAR	’27 proj	2027
62	Yusei Kikuchi LAA · ’91	101	1.1	1.0	Signed $21.0M
59	Jeffrey Springs ATH · ’92	96	−0.4	0.3	Free agent
56	Shane Drohan MIL · ’99	97	2.0	1.7	Pre-arb
56	Robbie Ray SD · ’91	96	0.9	0.7	Free agent
55	Gage Jump ATH · ’03	106	1.7	1.8	Pre-arb

Robbie Ray (similarity 56, 0.7 WAR projected for 2027) is a free agent this winter: a similar arsenal available without trading talent, at a free agent’s price. Opportunity Finder →

Same-handed pitchers nearest on fastball velocity and shape, arm angle, extension, pitch mix, secondary shapes, Stuff, whiff rate and workload. 2026 regulars only.

Pitch locations · 2026

Where each pitch finishes, by batter side

Four-seam 45%

49% zone

Changeup 22%

27% zone

Slider 18%

47% zone

Curveball 15%

48% zone

Where each pitch finishes, catcher’s view. The bar marks the batter’s side; the box is an average strike zone. Pitches with 40+ thrown to this side.

Contract & projection

Club control (RosterResource) · Keystone projected WAR

2027 1.1 WAR Pre-arb $780K*

2028 1.2 WAR Pre-arb $803K*

2029 1.2 WAR Pre-arb $828K*

2030 1.1 WAR Arbitration $2.8M*

* projected arbitration or minimum salary. Contract Studio →

Minor leagues

MLB Stats API · public box-score data

SeasonLevel	Level	Team	Age	G	PA / IP	PA / IP ·Line
2026AAA	AAA	Memphis Redbirds	25	21	99 IP	99 IP · 3.27 ERA · 29.2% K · 14.8% BB
2025A	A	Palm Beach Cardinals	24	1	3 IP	3 IP · 0.00 ERA · 36.4% K · 0.0% BB
2025AAA	AAA	Memphis Redbirds	24	22	94 IP	94 IP · 3.93 ERA · 25.4% K · 17.5% BB
2025ROK	ROK	FCL Cardinals	24	1	2 IP	2 IP · 0.00 ERA · 57.1% K · 0.0% BB

FanGraphs: FV 45 · ETA 2026. Public pitch tracking exists only at Triple-A and some Florida State League parks.