most losses single season for a rookie pitcher

John Coleman has lost the most games by a rookie, with 48 games in 1883.

	NAME	L	SEASON	TM	W	L%	G	W%	GS	ERA	SO	CG	SHO	SV	IP	H	ER	R	HR	BB	HBP	GF	TBF	WP	K/9	BB/9	K/BB	HR/9	K%	BB%	WHIP	BABIP	RA	ERA-	FIP	FIP-	H/9	PRAA
1	John Coleman J. Coleman	48	1883	PHN	12	.800	65	.200	61	4.87	159	59	3	0	538.1	772	291	510	17	48		4	2,546	9	2.66	0.80	3.31	0.28	6.2	1.9	1.52		8.53	158	3.34	109	12.91	-19.2
2	Larry McKeon L. McKeon	41	1884	IND	18	.695	61	.305	60	3.50	308	59	2	0	512.0	488	199	350	20	94	18	1	2,185	36	5.41	1.65	3.28	0.35	14.1	4.3	1.14	.268	6.15	108	3.24	101	8.58	-1.7
3	George Cobb G. Cobb	37	1892	BAL	10	.787	53	.213	47	4.86	159	42	0	0	394.1	495	213	333	21	140	19	6	1,836	15	3.63	3.20	1.14	0.48	8.7	7.6	1.61	.317	7.60	145	3.53	105	11.30	-6.1
4	Kid Carsey K. Carsey	37	1891	WSH	14	.725	54	.275	53	4.99	174	46	1	0	415.0	513	230	358	17	161	28	1	1,937	29	3.77	3.49	1.08	0.37	9.0	8.3	1.62	.319	7.76	133	3.59	99	11.13	2.3
5	Fleury Sullivan F. Sullivan	35	1884	PIT	16	.686	51	.314	51	4.20	189	51	2	0	441.0	496	206	328	15	96	20	0	1,967	25	3.86	1.96	1.97	0.31	9.6	4.9	1.34	.292	6.69	131	3.65	115	10.12	-24.7
6	Adonis Terry A. Terry	35	1884	BKN	19	.648	56	.352	55	3.55	230	54	2	0	476.0	486	188	308	10	72	8	1	2,049	33	4.35	1.36	3.19	0.19	11.2	3.5	1.17	.275	5.82	110	3.09	96	9.19	6.4
7	Jim Devlin J. Devlin	35	1876	LOU	30	.538	68	.462	68	1.56	122	66	5	0	622.0	566	108	309	3	37		0	2,568	14	1.77	0.54	3.30	0.04	4.8	1.4	0.97		4.47	62	2.08	82	8.19	50.7
8	Matt Kilroy M. Kilroy	34	1886	BAL	29	.540	68	.460	68	3.37	513	66	5	0	583.0	476	218	350	10	182	19	0	2,469	61	7.92	2.81	2.82	0.15	20.8	7.4	1.13	.267	5.40	100	2.60	77	7.35	47
9	Bobby Mathews B. Mathews	34	1876	NYM	21	.618	56	.382	56	2.86	37	55	2	0	516.0	693	164	395	8	24		0	2,327	3	0.65	0.42	1.54	0.14	1.6	1.0	1.39		6.89	128	2.43	109	12.09	-17.6
10	Hardie Henderson H. Henderson	33	1883	TOT	10	.767	46	.233	43	4.39	147	39	0	0	367.1	409	179	339	4	89		3	1,638	32	3.60	2.18	1.65	0.10	9.0	5.4	1.36		8.31	134	3.32	101	10.02	-1.4
11	Jim Whitney J. Whitney	33	1881	BOS	31	.516	66	.484	63	2.48	162	57	6	0	552.1	548	152	284	6	90		3	2,301	46	2.64	1.47	1.80	0.10	7.0	3.9	1.16		4.63	90	2.73	99	8.93	-0.4
12	Harry McCormick H. McCormick	33	1879	SYR	18	.647	54	.353	54	2.99	96	49	5	0	457.1	517	152	291	3	31		4	1,975	31	1.89	0.61	3.10	0.06	4.9	1.6	1.20		5.73	126	2.61	110	10.17	-20.1
13	John Harkins J. Harkins	32	1884	CLE	12	.727	46	.273	45	3.68	192	42	3	0	391.0	399	160	300	7	108		1	1,709	48	4.42	2.49	1.78	0.16	11.2	6.3	1.30		6.91	126	3.35	101	9.18	-3.4
14	Lee Richmond L. Richmond	32	1880	WOR	32	.500	74	.500	66	2.15	243	57	5	3	590.2	541	141	278	7	74		9	2,410	29	3.70	1.13	3.28	0.11	10.1	3.1	1.04		4.24	85	2.24	88	8.24	28.7
15	Billy Crowell B. Crowell	31	1887	CLE	14	.689	45	.311	45	4.88	72	45	1	0	389.1	541	211	350	9	138	20	0	1,812	23	1.66	3.19	0.52	0.21	4.0	7.6	1.74	.338	8.09	114	4.42	107	12.51	-13.2
16	Sam Weaver S. Weaver	31	1878	MIL	12	.721	45	.279	43	1.95	95	39	1	0	383.0	371	83	214	2	21		2	1,589	25	2.23	0.49	4.52	0.05	6.0	1.3	1.02		5.03	79	2.27	92	8.72	15.6
17	Mickey Welch M. Welch	30	1880	TRO	34	.469	65	.531	64	2.54	123	64	4	0	574.0	575	162	321	7	80		1	2,387	26	1.93	1.25	1.54	0.11	5.2	3.4	1.14		5.03	103	2.68	109	9.02	-7.1
18	Ellsworth Cunningham E. Cunningham	29	1888	BAL	22	.569	51	.431	51	3.39	186	50	0	0	453.1	412	171	275	8	157	30	0	1,952	47	3.69	3.12	1.18	0.16	9.5	8.0	1.26	.257	5.46	113	3.23	112	8.18	-20.2
19	Doc Landis D. Landis	29	1882	TOT	12	.707	44	.293	42	3.36	74	37	0	0	359.0	427	134	267	8	49		2	1,592	32	1.86	1.23	1.51	0.20	4.6	3.1	1.33		6.69	127	3.05	110	10.70	-13.4
20	Bill Hill B. Hill	28	1896	LOU	9	.757	43	.243	39	4.31	104	32	0	2	319.2	353	153	229	14	155	18	3	1,444	9	2.93	4.36	0.67	0.39	7.2	10.7	1.59	.294	6.45	103	4.83	116	9.94	-26.9
21	Gus Weyhing G. Weyhing	28	1887	PHA	26	.519	55	.481	55	4.27	193	53	2	0	466.1	465	221	342	12	167	37	0	2,042	49	3.72	3.22	1.16	0.23	9.5	8.2	1.36	.277	6.60	99	4.10	99	8.97	1.2
22	Hank O'Day H. O'Day	28	1884	TOL	9	.757	41	.243	40	3.75	163	35	2	1	326.2	335	136	241	6	66	18	1	1,412	40	4.49	1.82	2.47	0.17	11.5	4.7	1.23	.284	6.64	113	3.29	101	9.23	1.2
23	Bill Carrick B. Carrick	27	1899	NYG	16	.628	44	.372	43	4.65	60	40	3	0	361.2	485	187	250	4	122	18	1	1,654	11	1.49	3.04	0.49	0.10	3.6	7.4	1.68	.332	6.22	125	3.91	105	12.07	-9.4
24	Chick Fraser C. Fraser	27	1896	LOU	12	.692	43	.308	38	4.87	91	36	0	1	349.1	396	189	282	9	166	29	5	1,594	27	2.34	4.28	0.55	0.23	5.7	10.4	1.61	.298	7.27	116	4.78	114	10.20	-27.2
25	Park Swartzel P. Swartzel	27	1889	KCC	19	.587	48	.413	47	4.32	147	45	0	1	410.1	481	197	334	21	117	23	1	1,837	37	3.22	2.57	1.26	0.46	8.0	6.4	1.46	.301	7.33	106	3.98	98	10.55	9.2