most losses single season for a rookie pitcher 2000 to 2025

Since 2000, Jeremy Bonderman lost the most games by a rookie, with 19 games in 2003.

	NAME	L	SEASON	TM	W	L%	G	W%	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	ERA-	FIP	FIP-	H/9	PRAA
1	Jeremy Bonderman J. Bonderman	19	2003	DET	6	.760	33	.240	28	5.56	108	0	0	0	162.0	193	100	118	23	58	4	0	2	727	12	6.00	3.22	1.86	1.28	14.9	8.0	1.55	.318	6.56	127	4.69	106	10.72	-5
2	Spencer Turnbull S. Turnbull	17	2019	DET	3	.850	30	.150	30	4.61	146	0	0	0	148.1	154	76	86	14	59	16	0	1	656	9	8.86	3.58	2.47	0.85	22.3	9.0	1.44	.333	5.22	100	3.98	87	9.34	9.7
3	Greg Smith G. Smith	16	2008	OAK	7	.696	32	.304	32	4.16	111	2	0	0	190.1	169	88	92	21	87	3	0	5	800	5	5.25	4.11	1.28	0.99	13.9	10.9	1.35	.256	4.35	99	4.81	114	7.99	-12.7
4	Cole Irvin C. Irvin	15	2021	OAK	10	.600	32	.400	32	4.24	125	0	0	0	178.1	195	84	94	23	42	9	0	0	768	3	6.31	2.12	2.98	1.16	16.3	5.5	1.33	.302	4.74	103	4.29	104	9.84	-3.2
5	Wily Peralta W. Peralta	15	2013	MIL	11	.577	32	.423	32	4.37	129	2	1	0	183.1	187	89	107	19	73	7	0	3	802	12	6.33	3.58	1.77	0.93	16.1	9.1	1.42	.293	5.25	112	4.29	110	9.18	-7.2
6	John Lannan J. Lannan	15	2008	WSH	9	.625	31	.375	31	3.91	117	0	0	0	182.0	172	79	89	23	72	7	0	1	779	6	5.79	3.56	1.63	1.14	15.0	9.2	1.34	.266	4.40	91	4.78	110	8.51	-8.5
7	Chris Reitsma C. Reitsma	15	2001	CIN	7	.682	36	.318	29	5.29	96	0	0	0	182.0	209	107	121	23	49	5	1	6	800	5	4.75	2.42	1.96	1.14	12.0	6.1	1.42	.297	5.98	119	4.52	100	10.34	0.4
8	Sandy Alcantara S. Alcantara	14	2019	MIA	6	.700	32	.300	32	3.88	151	2	2	0	197.1	179	85	94	23	81	8	0	5	838	4	6.89	3.69	1.86	1.05	18.0	9.7	1.32	.271	4.29	93	4.54	106	8.16	-5.9
9	Merrill Kelly M. Kelly	14	2019	ARI	13	.519	32	.481	32	4.42	158	0	0	0	183.1	184	90	95	29	57	2	0	4	777	4	7.76	2.80	2.77	1.42	20.3	7.3	1.31	.292	4.66	100	4.50	104	9.03	-3.6
10	Johnny Cueto J. Cueto	14	2008	CIN	9	.609	31	.391	31	4.81	158	0	0	0	174.0	178	93	101	29	68	14	0	1	769	6	8.17	3.52	2.32	1.50	20.5	8.8	1.41	.298	5.22	109	4.89	110	9.21	-8.1
11	Spencer Arrighetti S. Arrighetti	13	2024	HOU	7	.650	29	.350	28	4.53	171	0	0	0	145.0	139	73	80	21	65	7	0	0	632	3	10.61	4.03	2.63	1.30	27.1	10.3	1.41	.321	4.97	114	4.17	103	8.63	-2.1
12	Joey Wentz J. Wentz	13	2023	DET	3	.813	25	.188	19	6.90	98	0	0	0	105.2	131	81	87	25	47	0	0	0	492	2	8.35	4.00	2.09	2.13	19.9	9.6	1.68	.329	7.41	163	5.81	137	11.16	-18.6
13	Hunter Brown H. Brown	13	2023	HOU	11	.542	31	.458	29	5.09	178	0	0	0	155.2	157	88	94	26	55	9	1	0	665	4	10.29	3.18	3.24	1.50	26.8	8.3	1.36	.330	5.43	120	4.37	103	9.08	-2.3
14	Hunter Greene H. Greene	13	2022	CIN	5	.722	24	.278	24	4.44	164	1	1	0	125.2	104	62	64	24	48	10	0	0	531	4	11.75	3.44	3.42	1.72	30.9	9.0	1.21	.281	4.58	104	4.36	104	7.45	-2.1
15	Adbert Alzolay A. Alzolay	13	2021	CHC	5	.722	29	.278	21	4.58	128	0	0	1	125.2	112	64	66	25	34	5	1	2	519	2	9.17	2.44	3.76	1.79	24.7	6.6	1.16	.266	4.73	110	4.64	111	8.02	-6.3
16	JT Brubaker	13	2021	PIT	5	.722	24	.278	24	5.36	129	0	0	0	124.1	123	74	75	28	38	9	0	1	538	3	9.34	2.75	3.39	2.03	24.0	7.1	1.29	.284	5.43	126	5.15	121	8.90	-12.6
17	Andrew Suárez A. Suárez	13	2018	SFG	7	.650	29	.350	29	4.49	130	0	0	0	160.1	163	80	85	23	45	3	0	1	665	4	7.30	2.53	2.89	1.29	19.5	6.8	1.30	.302	4.77	115	4.30	111	9.15	-8.5
18	Anthony DeSclafani A. DeSclafani	13	2015	CIN	9	.591	31	.409	31	4.05	151	0	0	0	184.2	194	83	93	17	55	5	0	5	785	6	7.36	2.68	2.75	0.83	19.2	7.0	1.35	.318	4.53	103	3.66	93	9.45	6
19	Jake Odorizzi J. Odorizzi	13	2014	TBR	11	.542	31	.458	31	4.13	174	0	0	0	168.0	156	77	79	20	59	5	0	0	719	3	9.32	3.16	2.95	1.07	24.2	8.2	1.28	.295	4.23	111	3.75	102	8.36	-1.6
20	Nathan Eovaldi N. Eovaldi	13	2012	TOT	4	.765	22	.235	22	4.30	78	0	0	0	119.1	133	57	59	10	47	3	0	3	526	1	5.88	3.54	1.66	0.75	14.8	8.9	1.51	.317	4.45	112	4.13	108	10.03	-4
21	Mitch Talbot M. Talbot	13	2010	CLE	10	.565	28	.435	28	4.41	88	1	0	0	159.1	169	78	88	13	69	8	0	2	696	3	4.97	3.90	1.28	0.73	12.6	9.9	1.49	.301	4.97	110	4.48	110	9.55	-7.3
22	Trevor Cahill T. Cahill	13	2009	OAK	10	.565	32	.435	32	4.63	90	0	0	0	178.2	185	92	99	27	72	4	0	1	773	5	4.53	3.63	1.25	1.36	11.6	9.3	1.44	.272	4.99	107	5.32	123	9.32	-20.4
23	Derek Holland D. Holland	13	2009	TEX	8	.619	33	.381	21	6.12	107	1	1	0	138.1	160	94	98	26	47	4	0	0	611	3	6.96	3.06	2.28	1.69	17.5	7.7	1.50	.314	6.38	131	5.09	112	10.41	-8
24	John Danks J. Danks	13	2007	CWS	6	.684	26	.316	26	5.50	109	0	0	0	139.0	160	85	92	28	54	4	0	4	622	3	7.06	3.50	2.02	1.81	17.5	8.7	1.54	.309	5.96	119	5.53	119	10.36	-12.6
25	Chase Dollander C. Dollander	12	2025	COL	2	.857	21	.143	21	6.52	82	0	0	0	98.0	103	71	76	18	49	6	0	0	441	2	7.53	4.50	1.67	1.65	18.6	11.1	1.55	.297	6.98	137	5.53	127	9.46	-12.1