Rafael Soriano had the lowest WHIP by a rookie with more than 35.0 innings pitched in 2003, with a WHIP of 0.79.

	NAME	WHIP	IP	SEASON	TM	G	W	L	W%	GS	ERA	SO	CG	SHO	SV	H	ER	R	HR	BB	HBP	GF	IBB	TBF	WP	K/9	BB/9	K/BB	HR/9	K%	BB%	BABIP	RA	ERA-	FIP	FIP-	H/9	PRAA
1	Rafael Soriano R. Soriano	0.79	53.0	2003	SEA	40	3	0	1.000	0	1.53	68	0	0	1	30	9	9	2	12	3	12	1	201	0	11.55	2.04	5.67	0.34	33.8	6.0	.241	1.53	36	1.80	41	5.09	15.4
2	Julio Mateo J. Mateo	0.96	85.2	2003	SEA	50	4	0	1.000	0	3.15	71	0	0	1	69	30	32	14	13	5	17	1	338	1	7.46	1.37	5.46	1.47	21.0	3.8	.234	3.36	73	4.12	94	7.25	2.3
3	Francisco Rodriguez F. Rodriguez	0.99	86.0	2003	ANA	59	8	3	.727	0	3.03	95	0	0	2	50	29	30	12	35	2	23	5	334	7	9.94	3.66	2.71	1.26	28.4	10.5	.200	3.14	68	3.92	89	5.23	4.8
4	Jose Valverde J. Valverde	0.99	50.1	2003	ARI	54	2	1	.667	0	2.15	71	0	0	10	24	12	16	4	26	2	33	2	204	2	12.70	4.65	2.73	0.72	34.8	12.7	.198	2.86	48	2.91	65	4.29	8.5
5	Rafael Betancourt R. Betancourt	1.05	38.0	2003	CLE	33	2	2	.500	0	2.13	36	0	0	1	27	9	11	5	13	1	13	2	154	1	8.53	3.08	2.77	1.18	23.4	8.4	.222	2.61	48	3.95	90	6.39	1.8
6	Jason Kershner J. Kershner	1.07	54.0	2003	TOR	40	3	3	.500	0	3.17	32	0	0	0	43	19	21	5	15	2	8	2	220	2	5.33	2.50	2.13	0.83	14.5	6.8	.229	3.50	68	3.99	88	7.17	3.4
7	Luis Ayala L. Ayala	1.10	71.0	2003	MON	65	10	3	.769	0	2.92	46	0	0	5	65	23	27	8	13	5	24	3	288	1	5.83	1.65	3.54	1.01	16.0	4.5	.264	3.42	66	3.95	89	8.24	3.7
8	Erasmo Ramirez E. Ramirez	1.12	49.0	2003	TEX	34	3	1	.750	0	3.86	28	0	0	0	46	21	21	4	9	4	9	0	200	1	5.14	1.65	3.11	0.73	14.0	4.5	.271	3.86	80	3.74	81	8.45	4.6
9	Brandon Webb B. Webb	1.15	180.2	2003	ARI	29	10	9	.526	28	2.84	172	1	1	0	140	57	65	12	68	13	1	4	750	9	8.57	3.39	2.53	0.60	22.9	9.1	.264	3.24	63	3.33	75	6.97	22.3
10	Lance Carter L. Carter	1.15	79.0	2003	TBD	62	7	5	.583	0	4.33	47	0	0	26	72	38	39	12	19	4	55	6	328	0	5.35	2.16	2.47	1.37	14.3	5.8	.244	4.44	97	4.68	106	8.20	-2.4
11	Eric DuBose E. DuBose	1.15	73.2	2003	BAL	17	3	6	.333	10	3.79	44	1	0	0	60	31	33	6	25	5	3	2	305	0	5.38	3.05	1.76	0.73	14.4	8.2	.240	4.03	86	4.11	90	7.33	3.6
12	Jose Contreras J. Contreras	1.15	71.0	2003	NYY	18	7	2	.778	9	3.30	72	0	0	0	52	26	27	4	30	5	2	1	293	2	9.13	3.80	2.40	0.51	24.6	10.2	.264	3.42	74	3.21	72	6.59	9.9
13	Cliff Lee C. Lee	1.17	52.1	2003	CLE	9	3	3	.500	9	3.61	44	0	0	0	41	21	28	7	20	2	0	1	210	3	7.57	3.44	2.20	1.20	21.0	9.5	.248	4.82	81	4.34	99	7.05	0.1
14	Brad Lidge B. Lidge	1.20	85.0	2003	HOU	78	6	3	.667	0	3.60	97	0	0	1	60	34	36	6	42	5	9	7	349	4	10.27	4.45	2.31	0.64	27.8	12.0	.271	3.81	82	3.32	76	6.35	9.9
15	Javier Lopez J. Lopez	1.20	58.1	2003	COL	75	4	1	.800	0	3.70	40	0	0	1	58	24	25	5	12	4	11	2	242	1	6.17	1.85	3.33	0.77	16.5	5.0	.293	3.86	75	3.59	77	8.95	6.5
16	Doug Waechter D. Waechter	1.25	35.1	2003	TBD	6	3	2	.600	5	3.31	29	1	1	0	29	13	13	4	15	1	0	0	145	0	7.39	3.82	1.93	1.02	20.0	10.3	.260	3.31	74	4.21	95	7.39	0.8
17	Aquilino Lopez A. Lopez	1.25	73.2	2003	TOR	72	1	3	.250	0	3.42	64	0	0	14	58	28	31	5	34	5	34	5	316	2	7.82	4.15	1.88	0.61	20.3	10.8	.255	3.79	73	3.76	83	7.09	6.4
18	Jerome Williams J. Williams	1.26	131.0	2003	SFG	21	7	5	.583	21	3.30	88	2	1	0	116	48	54	10	49	7	0	3	545	2	6.05	3.37	1.80	0.69	16.1	9.0	.271	3.71	79	3.96	95	7.97	2.9
19	Jae Weong Seo J. Weong Seo	1.27	188.1	2003	NYM	32	9	12	.429	31	3.82	110	0	0	0	193	80	94	18	46	6	0	11	806	2	5.26	2.20	2.39	0.86	13.6	5.7	.280	4.49	92	3.93	92	9.22	6.7
20	Kiko Calero K. Calero	1.28	38.1	2003	STL	26	1	1	.500	1	2.82	51	0	0	1	29	12	12	5	20	1	7	2	162	3	11.97	4.70	2.55	1.17	31.5	12.3	.282	2.82	67	3.70	87	6.81	2.3
21	Jason Stanford J. Stanford	1.28	50.0	2003	CLE	13	1	3	.250	8	3.60	30	0	0	0	48	20	20	5	16	1	1	1	213	0	5.40	2.88	1.88	0.90	14.1	7.5	.267	3.60	81	4.14	95	8.64	1.2
22	Dontrelle Willis D. Willis	1.28	160.2	2003	FLA	27	14	6	.700	27	3.30	142	2	2	0	148	59	61	13	58	3	0	0	668	7	7.95	3.25	2.45	0.73	21.3	8.7	.299	3.42	80	3.45	82	8.29	13.7
23	Oscar Villarreal O. Villarreal	1.29	98.0	2003	ARI	86	10	7	.588	1	2.57	80	0	0	0	80	28	40	6	46	3	14	10	422	3	7.35	4.22	1.74	0.55	19.0	10.9	.258	3.67	57	3.69	83	7.35	8.3
24	Chris Spurling C. Spurling	1.30	77.0	2003	DET	66	1	3	.250	0	4.68	38	0	0	3	78	40	42	9	22	3	18	1	326	2	4.44	2.57	1.73	1.05	11.7	6.7	.272	4.91	107	4.53	103	9.12	-1
25	Juan Rincon J. Rincon	1.31	85.2	2003	MIN	58	5	6	.455	0	3.68	63	0	0	0	74	35	38	5	38	4	20	7	370	7	6.62	3.99	1.66	0.53	17.0	10.3	.265	3.99	80	3.78	87	7.77	5.2