lowest single season era by 40+ year old pitcher

Cy Young has the best ERA by a pitcher 40 or older in a season, with an ERA of 1.26 in 1908.

Interpreted as:

lowest single season era with a minimum of 1 IP per team game by 40+ year old pitcher

	NAME	ERA	AGE	SEASON	TM	G	W	L	W%	GS	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	ERA-	FIP	FIP-	H/9	PRAA
1	Cy Young C. Young	1.26	41	1908	BOS	36	21	11	.656	33	150	30	3	2	299.0	230	42	68	1	37	1	3		1,116	4	4.52	1.11	4.05	0.03	13.4	3.3	0.89	.247	2.05	52	1.52	67	6.92	25.4
2	Roger Clemens R. Clemens	1.87	42	2005	HOU	32	13	8	.619	32	185	1	0	0	211.1	151	44	51	11	62	3	0	5	838	3	7.88	2.64	2.98	0.47	22.1	7.4	1.01	.243	2.17	44	2.86	67	6.43	33.4
3	Cy Young C. Young	1.99	40	1907	BSA	43	21	15	.583	37	147	33	6	2	343.1	286	76	101	3	51	7	5		1,308	6	3.85	1.34	2.88	0.08	11.2	3.9	0.98	.257	2.65	77	1.94	80	7.50	18.8
4	Ted Lyons T. Lyons	2.10	41	1942	CWS	20	14	6	.700	20	50	20	1	0	180.1	167	42	52	11	26	2	0		720	3	2.50	1.30	1.92	0.55	6.9	3.6	1.07	.247	2.60	58	3.12	89	8.33	7.3
5	Cy Young C. Young	2.26	42	1909	CLE	35	19	15	.559	34	109	30	3	0	294.1	267	74	110	4	59	8	1		1,137	6	3.33	1.80	1.85	0.12	9.6	5.2	1.11	.275	3.36	92	2.34	98	8.16	1
6	Johnny Niggeling J. Niggeling	2.32	40	1944	WSH	24	10	8	.556	24	121	14	2	0	206.0	164	53	65	5	88	4	0		848	5	5.29	3.84	1.38	0.22	14.3	10.4	1.22	.252	2.84	70	3.02	92	7.17	5.7
7	Eddie Plank E. Plank	2.33	40	1916	SLA	37	16	15	.516	26	88	17	3	3	235.2	203	61	78	2	67	6	9		930	2	3.36	2.56	1.31	0.08	9.5	7.2	1.15	.262	2.98	84	2.61	95	7.75	3.5
8	Grover Alexander G. Alexander	2.52	40	1927	SLN	37	21	10	.677	30	48	22	2	3	268.0	261	75	94	11	38	1	5		1,082	1	1.61	1.28	1.26	0.37	4.4	3.5	1.12	.254	3.16	64	3.64	91	8.76	10.6
9	Cy Young C. Young	2.53	43	1910	CLE	21	7	10	.412	20	58	14	1	0	163.1	149	46	62	0	27	4	0		623	7	3.20	1.49	2.15	0.00	9.3	4.3	1.08	.279	3.42	99	2.18	83	8.21	8.6
10	Warren Spahn W. Spahn	2.60	42	1963	MIL	33	23	7	.767	33	102	22	7	0	259.2	241	75	85	23	49	0	0	4	1,037	4	3.54	1.70	2.08	0.80	9.8	4.7	1.12	.253	2.95	81	3.41	106	8.35	-6.4
11	Randy Johnson R. Johnson	2.60	40	2004	ARI	35	16	14	.533	35	290	4	2	0	245.2	177	71	88	18	44	10	0	1	964	3	10.62	1.61	6.59	0.66	30.1	4.6	0.90	.264	3.22	57	2.29	51	6.48	59.7
12	Bartolo Colon B. Colon	2.65	40	2013	OAK	30	18	6	.750	30	117	3	3	0	190.1	193	56	60	14	29	0	0	0	769	1	5.53	1.37	4.03	0.66	15.2	3.8	1.17	.294	2.84	68	3.23	83	9.13	14
13	Nolan Ryan N. Ryan	2.76	40	1987	HOU	34	8	16	.333	34	270	0	0	0	211.2	154	65	75	14	87	4	0	2	873	10	11.48	3.70	3.10	0.60	30.9	10.0	1.14	.281	3.19	70	2.46	63	6.55	34.5
14	Connie Marrero C. Marrero	2.88	41	1952	WSH	22	11	8	.579	22	77	16	2	0	184.1	175	59	68	9	53	4	0		771	2	3.76	2.59	1.45	0.44	10.0	6.9	1.24	.264	3.32	80	3.12	86	8.54	10.4
15	Jack Quinn J. Quinn	2.90	45	1928	PHA	31	18	7	.720	28	43	18	4	1	211.1	239	68	92	3	34	7	2		898	0	1.83	1.45	1.26	0.13	4.8	3.8	1.29	.291	3.92	71	3.27	83	10.18	16.1
16	Nolan Ryan N. Ryan	2.91	44	1991	TEX	27	12	6	.667	27	203	2	2	0	173.0	102	56	58	12	72	5	0	0	683	8	10.56	3.75	2.82	0.62	29.7	10.5	1.01	.230	3.02	72	2.74	68	5.31	24.4
17	Rick Reuschel R. Reuschel	2.94	40	1989	SFG	32	17	8	.680	32	111	2	0	0	208.1	195	68	75	18	54	2	0	4	860	1	4.80	2.33	2.06	0.78	12.9	6.3	1.20	.262	3.24	88	3.62	102	8.42	-1.5
18	Roger Clemens R. Clemens	2.98	41	2004	HOU	33	18	4	.818	33	218	0	0	0	214.1	169	71	76	15	79	6	0	5	878	5	9.15	3.32	2.76	0.63	24.8	9.0	1.16	.275	3.19	69	3.11	70	7.10	31.7
19	Warren Spahn W. Spahn	3.02	40	1961	MIL	38	21	13	.618	34	115	21	4	0	262.2	236	88	96	24	64	4	3	1	1,064	4	3.94	2.19	1.80	0.82	10.8	6.0	1.14	.247	3.29	79	3.66	98	8.09	1.6
20	Warren Spahn W. Spahn	3.04	41	1962	MIL	34	18	14	.563	34	118	22	0	0	269.1	248	91	97	25	55	3	0	4	1,088	4	3.94	1.84	2.15	0.84	10.8	5.1	1.13	.251	3.24	80	3.59	98	8.29	2.2
21	Gaylord Perry G. Perry	3.06	40	1979	SDP	32	12	11	.522	32	140	10	0	0	232.2	225	79	90	12	67	4	0	10	963	6	5.42	2.59	2.09	0.46	14.5	7.0	1.26	.288	3.48	87	3.10	86	8.70	13.3
22	Dennis Martinez D. Martinez	3.08	40	1995	CLE	28	12	5	.706	28	99	3	2	0	187.0	174	64	71	17	46	12	0	2	771	3	4.76	2.21	2.15	0.82	12.8	6.0	1.18	.263	3.42	65	4.15	90	8.37	10
23	Phil Niekro P. Niekro	3.09	45	1984	NYY	32	16	8	.667	31	136	5	1	0	215.2	219	74	85	15	76	3	1	0	916	2	5.68	3.17	1.79	0.63	14.8	8.3	1.37	.297	3.55	80	3.50	89	9.14	10.3
24	Phil Niekro P. Niekro	3.10	42	1981	ATL	22	7	7	.500	22	62	3	3	0	139.1	120	48	56	6	56	1	0	2	578	2	4.00	3.62	1.11	0.39	10.7	9.7	1.26	.252	3.62	85	3.49	96	7.75	2.3
25	John Smoltz J. Smoltz	3.11	40	2007	ATL	32	14	8	.636	32	197	0	0	0	205.2	196	71	78	18	47	4	0	9	853	8	8.62	2.06	4.19	0.79	23.1	5.5	1.18	.303	3.41	71	3.19	72	8.58	28.7