highest winning number of wins without a loss in a single season by pitcher

Jack Chesbro has the most wins in wins in a season, with 41 wins in 1904.

	NAME	W	L	SEASON	TM	W%	L%	G	GS	ERA	SO	CG	SHO	SV	IP	H	ER	R	HR	BB	HBP	GF	IBB	TBF	WP	K/9	BB/9	K/BB	HR/9	K%	BB%	WHIP	BABIP	RA	H/9
1	Jack Chesbro J. Chesbro	41	0	1904	NYH	1.000	.000	41	38	1.17	193	38	6	0	354.2	232	46	64	4	66	5	3			5	4.90	1.67	2.92	0.10		5.0	0.84	.216	1.62	5.89
2	Ed Walsh E. Walsh	40	0	1908	CWS	1.000	.000	40	35		190	34	11	0	342.1	229		41	0	40	8	5		1,288	5	5.00	1.05	4.75	0.00	14.8	3.1	0.79	.218	1.08	6.02
3	Christy Mathewson C. Mathewson	37	0	1908	NYG	1.000	.000	37	32		204	29	11	0	298.1	188		33	1	26	3	5		1,116	2	6.15	0.78	7.85	0.03	18.3	2.3	0.72	.212	1.00	5.67
4	Walter Johnson W. Johnson	36	0	1913	WSH	1.000	.000	36	29	0.56	185	23	11	0	273.2	164	17	27	5	34	5	7		1,002	1	6.08	1.12	5.44	0.16	18.5	3.4	0.72	.206	0.89	5.39
5	Joe McGinnity J. McGinnity	35	0	1904	NYG	1.000	.000	35	31		109	29	9	0	284.0	199		53	6	60	9	4		1,105	1	3.45	1.90	1.82	0.19	9.9	5.4	0.91	.210	1.68	6.31
6	Joe Wood J. Wood	34	0	1912	BSA	1.000	.000	34	33	0.31	223	30	10	0	293.2	222		73	2	58	10	1		1,144	5	6.83	1.78	3.84	0.06	19.5	5.1	0.95	.259	2.24	6.80
7	Grover Alexander G. Alexander	33	0	1916	PHN	1.000	.000	33	33	0.83	139	33	16	0	302.0	216	28	36	2	33	5	0		1,118	3	4.14	0.98	4.21	0.06	12.4	3.0	0.82	.228	1.07	6.44
8	Walter Johnson W. Johnson	33	0	1912	WSH	1.000	.000	33	27	0.16	221	25	7	0	274.1	187		46	0	50	7	6		1,040	7	7.25	1.64	4.42	0.00	21.3	4.8	0.86	.245	1.51	6.13
9	Christy Mathewson C. Mathewson	33	0	1904	NYG	1.000	.000	33	31		151	23	4	0	256.2	183		50	5	53	4	2		992	4	5.29	1.86	2.85	0.18	15.2	5.3	0.92	.228	1.75	6.42
10	Cy Young C. Young	33	0	1901	BSA	1.000	.000	33	31	1.15	130	30	5	0	290.0	232	37	64	5	23	7	2			0	4.03	0.71	5.65	0.16		2.2	0.88	.256	1.99	7.20
11	Cy Young C. Young	32	0	1902	BSA	1.000	.000	32	32	1.38	133	32	3	0	299.0	232	46	71	2	39	6	0		1,149	2	4.00	1.17	3.41	0.06	11.6	3.4	0.91	.237	2.14	6.98
12	Denny McLain D. McLain	31	0	1968	DET	1.000	.000	31	31	1.62	236	28	6	0	273.0	186	49	54	20	46	5	0	1	1,031	3	7.78	1.52	5.13	0.66	22.9	4.5	0.85	.229	1.78	6.13
13	Lefty Grove L. Grove	31	0	1931	PHA	1.000	.000	31	27	1.80	144	25	4	0	255.1	212	51	69	8	59	1	4		1,021	1	5.08	2.08	2.44	0.28	14.1	5.8	1.06	.252	2.43	7.47
14	Jim Bagby J. Bagby	31	0	1920	CLE	1.000	.000	31	25	1.94	54	25	3	0	246.0	206	53	57	6	53	2	6		970	2	1.98	1.94	1.02	0.22	5.6	5.5	1.05	.234	2.09	7.54
15	Grover Alexander G. Alexander	31	0	1915	PHN	1.000	.000	31	30	0.85	179	29	12	0	276.0	170	26	45	2	44	4	1		1,037	1	5.84	1.43	4.07	0.07	17.3	4.2	0.78	.208	1.47	5.54
16	Jack Coombs J. Coombs	31	0	1910	PHA	1.000	.000	31	27		162	27	11	0	259.0	161		28	0	80	4	4		994	5	5.63	2.78	2.03	0.00	16.3	8.0	0.93	.215	0.97	5.59
17	Christy Mathewson C. Mathewson	31	0	1905	NYG	1.000	.000	31	29		163	25	8	0	254.2	167		45	3	49	0	2		962	3	5.76	1.73	3.33	0.11	16.9	5.1	0.85	.220	1.59	5.90
18	Joe McGinnity J. McGinnity	31	0	1903	NYG	1.000	.000	31	29		113	28	3	0	267.2	204		67	1	67	9	2		1,062	4	3.80	2.25	1.69	0.03	10.6	6.3	1.01	.233	2.25	6.86
19	Dizzy Dean D. Dean	30	0	1934	SLN	1.000	.000	30	26	1.65	153	23	7	0	251.1	195	46	56	9	49	4	4		999	1	5.48	1.75	3.12	0.32	15.3	4.9	0.97	.237	2.01	6.98
20	Grover Alexander G. Alexander	30	0	1917	PHN	1.000	.000	30	30	1.10	146	30	8	0	278.0	213	34	46	2	36	5	0		1,066	1	4.73	1.17	4.06	0.06	13.7	3.4	0.90	.241	1.49	6.90
21	Christy Mathewson C. Mathewson	30	0	1903	NYG	1.000	.000	30	28		176	25	3	0	251.1	206		71	3	61	5	2		1,007	15	6.30	2.18	2.89	0.11	17.5	6.1	1.06	.266	2.54	7.38
22	Hal Newhouser H. Newhouser	29	0	1944	DET	1.000	.000	29	25	1.82	156	24	6	0	242.2	194	49	52	5	57	1	4		956	3	5.79	2.11	2.74	0.19	16.3	6.0	1.03	.256	1.93	7.20
23	Eddie Cicotte E. Cicotte	29	0	1919	CWS	1.000	.000	29	27	1.00	86	27	5	0	252.2	186	28	39	5	37	3	2		963	0	3.06	1.32	2.32	0.18	8.9	3.8	0.88	.218	1.39	6.63
24	Claude Hendrix C. Hendrix	29	0	1914	CHF	1.000	.000	29	26	1.33	139	26	6	0	250.1	162	37	50	4	52	5	3			4	5.00	1.87	2.67	0.14		5.8	0.85	.226	1.80	5.82
25	George Mullin G. Mullin	29	0	1909	DET	1.000	.000	29	25		101	23	3	0	239.2	168		51	1	59	7	4		927	2	3.79	2.22	1.71	0.04	10.9	6.4	0.95	.220	1.92	6.31