Between the 1882 and 1956 seasons, Wilbur Cooper allowed the most earned runs for the Pirates, with 974 earned runs.

	NAME	ER	G	W	L	W%	GS	ERA	SO	CG	SHO	SV	IP	H	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	Wilbur Cooper W. Cooper	974	469	202	159	.560	369	2.74	1,191	263	33	14	3199.0	3,074	1,241	79	762	93	78		13,123	43	3.35	2.14	1.56	0.22	9.1	5.8	1.20	.272	3.49	84	3.03	93	8.65	90.3
2	Babe Adams B. Adams	911	481	194	139	.583	353	2.74	1,036	205	44	16	2991.1	2,832	1,125	67	428	47	90		11,926	26	3.12	1.29	2.42	0.20	8.7	3.6	1.09	.267	3.38	85	2.72	83	8.52	179.2
3	Ray Kremer R. Kremer	816	308	143	85	.627	247	3.76	516	134	14	9	1954.2	2,108	950	123	483	29	37		8,330	23	2.38	2.22	1.07	0.57	6.2	5.8	1.33	.277	4.37	88	4.18	97	9.71	23.9
4	Rip Sewell R. Sewell	804	385	143	97	.596	243	3.43	634	137	20	15	2108.2	2,082	968	114	740	23	86		9,041	30	2.71	3.16	0.86	0.49	7.0	8.2	1.34	.261	4.13	92	3.77	99	8.89	6.8
5	Frank Killen F. Killen	733	213	112	82	.577	201	3.97	467	163	9	0	1661.1	1,869	1,056	31	519	54	10		7,251	32	2.53	2.81	0.90	0.17	6.4	7.2	1.44	.297	5.72	92	4.03	92	10.13	51.6
6	Sam Leever S. Leever	731	388	194	100	.660	299	2.47	847	241	39	13	2660.2	2,449	1,023	29	587	88	75		10,662	46	2.87	1.99	1.44	0.10	7.9	5.5	1.14	.266	3.46	81	2.84	92	8.28	74.2
7	Pud Galvin P. Galvin	719	246	126	110	.534	241	3.10	434	225	17	0	2084.2	2,242	1,166	54	370	42	5		8,874	58	1.87	1.60	1.17	0.23	4.9	4.2	1.25	.275	5.03	95	3.43	103	9.68	-56.6
8	Ed Morris E. Morris	656	241	129	102	.558	240	2.81	890	235	25	1	2104.0	1,955	1,037	34	412	22	1		8,719	87	3.81	1.76	2.16	0.15	10.2	4.7	1.13	.262	4.44	88	2.95	94	8.36	9.7
9	Deacon Phillippe D. Phillippe	636	330	168	92	.646	251	2.50	861	209	25	11	2286.0	2,187	893	31	299	52	68		9,065	42	3.39	1.18	2.88	0.12	9.5	3.3	1.09	.276	3.52	85	2.46	81	8.61	149.2
10	Bill Swift B. Swift	616	305	91	79	.535	164	3.57	592	78	7	18	1555.0	1,596	712	94	310	30	106		6,519	9	3.43	1.79	1.91	0.54	9.1	4.8	1.23	.273	4.12	92	3.72	93	9.24	50.5
11	Larry French L. French	585	254	87	83	.512	183	3.50	475	104	15	9	1502.2	1,646	736	73	397	19	46		6,471	17	2.84	2.38	1.20	0.44	7.3	6.1	1.36	.286	4.41	85	3.94	95	9.86	35.2
12	Johnny Morrison J. Morrison	533	242	89	71	.556	154	3.52	478	85	13	14	1363.2	1,377	621	43	429	25	61		5,749	28	3.15	2.83	1.11	0.28	8.3	7.5	1.32	.279	4.10	87	3.72	92	9.09	50.4
13	Bob Friend B. Friend	530	229	59	76	.437	151	4.01	519	49	10	6	1190.1	1,244	616	104	404	11	37	22	5,119	16	3.92	3.05	1.28	0.79	10.1	7.9	1.38	.279	4.66	100	3.73	92	9.41	44.2
14	Murry Dickson M. Dickson	517	228	66	85	.437	137	3.83	477	69	8	11	1216.1	1,255	601	122	398	18	63		5,186	10	3.53	2.94	1.20	0.90	9.2	7.7	1.36	.272	4.45	91	4.05	96	9.29	25.4
15	Howie Camnitz H. Camnitz	513	277	116	84	.580	196	2.63	806	116	19	13	1754.1	1,528	689	31	532	55	69		7,036	33	4.13	2.73	1.52	0.16	11.5	7.6	1.17	.267	3.53	90	2.76	93	7.84	37.3
16	Lee Meadows L. Meadows	486	183	88	52	.629	157	3.50	355	93	8	1	1248.1	1,351	592	42	286	25	15		5,264	11	2.56	2.06	1.24	0.30	6.7	5.4	1.31	.287	4.27	86	3.62	88	9.74	67.1
17	Pink Hawley P. Hawley	473	145	71	61	.538	132	3.76	367	114	6	1	1133.2	1,193	660	16	373	87	12		4,920	32	2.91	2.96	0.98	0.13	7.5	7.6	1.38	.289	5.24	87	4.17	96	9.47	19.5
18	Jesse Tannehill J. Tannehill	461	192	116	58	.667	171	2.75	466	149	17	5	1508.0	1,561	663	11	243	71	20		6,182	10	2.78	1.45	1.92	0.07	7.5	3.9	1.20	.288	3.96	78	2.98	84	9.32	88.5
19	Heinie Meine H. Meine	437	164	66	50	.569	132	3.95	199	60	7	3	995.1	1,120	523	47	285	25	18		4,335	16	1.80	2.58	0.70	0.42	4.6	6.6	1.41	.284	4.73	98	4.23	104	10.13	-15.8
20	Max Butcher M. Butcher	435	202	67	60	.528	154	3.34	296	74	13	5	1171.2	1,249	517	52	328	11	27		5,035	11	2.27	2.52	0.90	0.40	5.9	6.5	1.35	.275	3.97	90	3.53	95	9.59	25.6
21	Erv Brame E. Brame	419	142	52	37	.584	91	4.76	188	62	3	0	791.2	946	492	62	232	6	34		3,504	9	2.14	2.64	0.81	0.70	5.4	6.6	1.49	.293	5.59	108	4.66	104	10.75	-14.9
22	Lefty Leifield L. Leifield	417	239	109	84	.565	191	2.38	546	125	28	7	1578.0	1,403	579	22	481	76	37		6,326	16	3.11	2.74	1.14	0.13	8.6	7.6	1.19	.266	3.30	86	2.91	102	8.00	-8.8
23	Bob Klinger B. Klinger	412	209	62	58	.517	129	3.74	329	48	7	9	990.2	1,062	489	40	309	18	46		4,275	21	2.99	2.81	1.06	0.36	7.7	7.2	1.38	.286	4.44	101	3.56	94	9.65	23.9
24	Red Ehret R. Ehret	411	124	53	59	.473	109	3.79	273	95	5	0	977.0	1,053	655	22	326	55	15		4,310	27	2.51	3.00	0.84	0.20	6.3	7.6	1.41	.284	6.03	86	4.09	94	9.70	22.8
25	Vern Law V. Law	405	176	40	57	.412	105	4.56	297	28	3	8	800.0	886	466	83	266	20	51	17	3,505	23	3.34	2.99	1.12	0.93	8.5	7.6	1.44	.283	5.24	113	4.10	100	9.97	2.1