Player stats

Knuckle curve: Average Spin 2018

How fast the ball spins, measured in turns per minute. Only measured pitches are included. More spin is not always better. Uses pitches recorded as knuckle curve.

Season

At least 100 pitches of this type with a spin measurement in this season. Recorded pitch types. Usage divides by all delivered pitches, including unknown types. Speed is in mph, spin in rpm and extension in feet. Averages use measured pitches only. Whiffs divide misses by swings. Data through December 31, 2018. Data refreshed Sep 9, 2026, 10:25 AM UTC.

No. 1 / Knuckle curve: Average Spin / 2018

Joe Kelly

BOS

3103

Season leader

Knuckle curve: Average Spin2018 season
#	Player	Team	KC spin count	Type coverage	KC rpm
1	J. KellyJoe Kelly	BOS	219	99.9%	3103
2	T. CahillTrevor Cahill	OAK	281	99.9%	2933
3	C. KuhlChad Kuhl	PIT	188	99.7%	2901
4	G. ColeGerrit Cole	HOU	626	100.0%	2842
5	N. PivettaNick Pivetta	PHI	617	98.9%	2837
6	J. HellicksonJeremy Hellickson	WSH	321	100.0%	2831
7	L. McCullers Jr.Lance McCullers Jr.	HOU	973	99.9%	2790
8	D. RobertsonDavid Robertson	NYY	414	100.0%	2772
9	W. BuehlerWalker Buehler	LAD	282	95.7%	2757
10	M. MelanconMark Melancon	SF	185	99.7%	2739
11	G. MárquezGermán Márquez	COL	707	99.9%	2689
12	R. StriplingRoss Stripling	LAD	419	96.5%	2652
13	C. KnebelCorey Knebel	MIL	287	99.9%	2623
14	I. KennedyIan Kennedy	KC	399	99.7%	2616
15	T. BauerTrevor Bauer	CLE	762	99.9%	2601
16	B. WorkmanBrandon Workman	BOS	238	100.0%	2593
17	C. KimbrelCraig Kimbrel	BOS	391	99.9%	2579
18	C. AllenCody Allen	CLE	450	95.9%	2575
19	D. CoulombeDanny Coulombe	OAK	114	100.0%	2571
20	A. CobbAlex Cobb	BAL	535	100.0%	2570
21	M. LeakeMike Leake	SEA	304	99.9%	2560
22	D. BetancesDellin Betances	NYY	315	99.9%	2555
23	W. DavisWade Davis	COL	239	99.6%	2549
24	A. NolaAaron Nola	PHI	992	100.0%	2545
25	S. SolísSammy Solís	WSH	144	100.0%	2541
26	T. DuffeyTyler Duffey	MIN	137	98.6%	2513
27	J. VargasJason Vargas	NYM	249	99.2%	2500
28	A. GomberAustin Gomber	STL	269	100.0%	2498
29	J. ShieldsJames Shields	CWS	621	99.9%	2478
30	J. JeffressJeremy Jeffress	MIL	373	100.0%	2464
31	M. MinorMike Minor	TEX	275	99.8%	2443
32	J. FlahertyJack Flaherty	STL	289	100.0%	2410
33	V. VelasquezVince Velasquez	PHI	382	100.0%	2406
34	S. CasillaSantiago Casilla	OAK	143	100.0%	2403
35	M. MooreMatt Moore	TEX	337	99.8%	2398
36	J. LópezJorge López	KC	236	99.8%	2374
37	B. CecilBrett Cecil	STL	208	100.0%	2352
38	C. StammenCraig Stammen	SD	124	96.0%	2327
39	M. BarnesMatt Barnes	BOS	450	99.9%	2319
40	N. KinghamNick Kingham	PIT	106	100.0%	2266
41	D. PomeranzDrew Pomeranz	BOS	564	99.9%	2221
42	Z. GodleyZack Godley	AZ	1195	100.0%	2178
43	F. SalasFernando Salas	AZ	101	100.0%	2167
44	D. HollandDerek Holland	SF	360	99.8%	2076
45	S. BieberShane Bieber	CLE	289	99.8%	2069
46	J. FieldsJosh Fields	LAD	116	95.5%	2061
47	A. WoodAlex Wood	LAD	746	100.0%	2049
48	R. RayRobbie Ray	AZ	464	99.8%	2025
49	A. BradleyArchie Bradley	AZ	218	99.8%	1979
50	J. PaxtonJames Paxton	SEA	559	99.7%	1949

KC rpm: How fast the ball spins, measured in turns per minute. Only measured pitches are included. More spin is not always better. Uses pitches recorded as knuckle curve.

Understanding Knuckle curve: Average Spin

How fast the ball spins, measured in turns per minute. Only measured pitches are included. More spin is not always better. Uses pitches recorded as knuckle curve.

Formula: Sum of recorded spin rates ÷ pitches with spin measurements

Read rates alongside playing time. A small sample can produce an extreme result, and a missing value is different from zero.

Season rankings use regular-season records. A player has one combined row across teams; the team label identifies the associated team, not a separate team stint.

Source: MLB statistics and MLBDB derived measures. Formulas describe the measure above. Data refreshed Sep 9, 2026, 10:25 AM UTC.