most wins in a season without a loss by a 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	43	39	1.24	198	39	6	0	362.2	243	50	73	4	68	5	3			6	4.91	1.69	2.91	0.10		5.0	0.86	.223	1.81	6.03
2	Ed Walsh E. Walsh	40	0	1908	CWS	1.000	.000	51	35		209	34	11	6	367.0	248		57	1	40	8	15		1,381	5	5.13	0.98	5.23	0.02	15.1	2.9	0.78	.220	1.40	6.08
3	Christy Mathewson C. Mathewson	37	0	1908	NYG	1.000	.000	45	34		224	30	11	3	320.0	206		42	3	30	3	9		1,201	2	6.30	0.84	7.47	0.08	18.7	2.5	0.74	.216	1.18	5.79
4	Walter Johnson W. Johnson	36	0	1913	WSH	1.000	.000	41	29	0.63	204	23	11	2	288.0	175	20	31	5	36	5	11		1,056	1	6.38	1.13	5.67	0.16	19.3	3.4	0.73	.211	0.97	5.47
5	Joe McGinnity J. McGinnity	35	0	1904	NYG	1.000	.000	43	36		127	31	9	3	338.1	251		70	6	72	10	7		1,329	2	3.38	1.92	1.76	0.16	9.6	5.4	0.95	.220	1.86	6.68
6	Joe Wood J. Wood	34	0	1912	BSA	1.000	.000	38	33	0.30	231	30	10	1	301.1	228		78	2	60	10	5		1,173	5	6.90	1.79	3.85	0.06	19.7	5.1	0.96	.260	2.33	6.81
7	Grover Alexander G. Alexander	33	0	1916	PHN	1.000	.000	36	33	0.83	139	33	16	3	303.2	217	28	36	2	33	5	3		1,122	3	4.12	0.98	4.21	0.06	12.4	2.9	0.82	.228	1.07	6.43
8	Walter Johnson W. Johnson	33	0	1912	WSH	1.000	.000	38	27	0.16	232	25	7	2	282.1	191		47	0	52	8	11		1,068	7	7.40	1.66	4.46	0.00	21.7	4.9	0.86	.246	1.50	6.09
9	Christy Mathewson C. Mathewson	33	0	1904	NYG	1.000	.000	36	34		161	24	4	0	282.2	207		58	5	57	4	2		1,095	6	5.13	1.81	2.82	0.16	14.7	5.2	0.93	.233	1.85	6.59
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	34	32	1.54	137	32	3	0	310.0	244	53	78	4	40	7	1			2	3.98	1.16	3.43	0.12		3.5	0.92	.250	2.26	7.08
12	Denny McLain D. McLain	31	0	1968	DET	1.000	.000	35	35	1.70	259	28	6	0	302.0	209	57	62	24	52	5	0	1	1,145	3	7.72	1.55	4.98	0.72	22.6	4.5	0.86	.230	1.85	6.23
13	Lefty Grove L. Grove	31	0	1931	PHA	1.000	.000	37	27	1.88	153	25	4	5	263.2	222	55	73	8	59	1	9		1,056	1	5.22	2.01	2.59	0.27	14.5	5.6	1.07	.256	2.49	7.58
14	Jim Bagby J. Bagby	31	0	1920	CLE	1.000	.000	36	28	2.25	59	25	3	0	268.1	246	67	73	6	60	3	8		1,079	3	1.98	2.01	0.98	0.20	5.5	5.6	1.14	.252	2.45	8.25
15	Grover Alexander G. Alexander	31	0	1915	PHN	1.000	.000	39	33	0.95	192	30	12	4	302.0	187	32	53	2	49	5	6		1,137	1	5.72	1.46	3.92	0.06	16.9	4.3	0.78	.208	1.58	5.57
16	Jack Coombs J. Coombs	31	0	1910	PHA	1.000	.000	36	30		193	30	13	1	297.2	181		37	0	99	6	5		1,144	8	5.84	2.99	1.95	0.00	16.9	8.7	0.94	.214	1.12	5.47
17	Christy Mathewson C. Mathewson	31	0	1905	NYG	1.000	.000	34	29		169	25	8	3	264.2	173		45	3	49	0	5		996	3	5.75	1.67	3.45	0.10	17.0	4.9	0.84	.219	1.53	5.88
18	Joe McGinnity J. McGinnity	31	0	1903	NYG	1.000	.000	35	30		116	28	3	2	274.1	208		69	1	70	11	5		1,093	4	3.81	2.30	1.66	0.03	10.6	6.4	1.01	.231	2.26	6.82
19	Dizzy Dean D. Dean	30	0	1934	SLN	1.000	.000	43	28	2.00	172	23	7	7	278.2	229	62	75	10	58	4	13		1,123	2	5.56	1.87	2.97	0.32	15.3	5.2	1.03	.249	2.42	7.40
20	Grover Alexander G. Alexander	30	0	1917	PHN	1.000	.000	32	31	1.16	149	30	8	0	288.0	218	37	49	3	38	5	0		1,102	1	4.66	1.19	3.92	0.09	13.5	3.4	0.89	.237	1.53	6.81
21	Christy Mathewson C. Mathewson	30	0	1903	NYG	1.000	.000	32	29		183	26	3	1	261.2	216		76	3	63	5	3		1,051	15	6.29	2.17	2.90	0.10	17.4	6.0	1.07	.267	2.61	7.43
22	Hal Newhouser H. Newhouser	29	0	1944	DET	1.000	.000	38	27	1.75	166	25	6	2	267.1	209	52	58	5	70	1	8		1,052	3	5.59	2.36	2.37	0.17	15.8	6.7	1.04	.252	1.95	7.04
23	Eddie Cicotte E. Cicotte	29	0	1919	CWS	1.000	.000	33	29	1.16	93	27	5	1	264.2	202	34	45	5	38	3	4		1,013	0	3.16	1.29	2.45	0.17	9.2	3.8	0.91	.225	1.53	6.87
24	Claude Hendrix C. Hendrix	29	0	1914	CHF	1.000	.000	38	28	1.34	153	27	6	5	282.0	182	42	61	4	61	6	10			5	4.88	1.95	2.51	0.13		6.5	0.86	.250	1.95	5.81
25	George Mullin G. Mullin	29	0	1909	DET	1.000	.000	32	27		103	23	3	1	244.0	179		59	1	63	8	5		952	3	3.80	2.32	1.63	0.04	10.8	6.6	0.99	.229	2.18	6.60