Since 1950, George Kirby has walked the worst walks per nine innings, with 1.13 BB/9.

Interpreted as:

fewest walks per 9 innings with a minimum of 0.5 IP per team game by a player since 1950

	NAME	BB/9	G	W	L	W%	GS	ERA	SO	CG	SHO	SV	IP	H	ER	R	HR	BB	HBP	GF	IBB	TBF	WP	K/9	K/BB	HR/9	K%	BB%	WHIP	BABIP	RA	ERA-	FIP	FIP-	H/9	PRAA
1	George Kirby G. Kirby	1.13	89	34	26	.567	89	3.43	484	1	0	0	511.2	495	195	210	57	64	18	0	1	2,077	10	8.51	7.56	1.00	23.3	3.1	1.09	.301	3.69	89	3.22	81	8.71	43.4
2	Josh Tomlin J. Tomlin	1.29	286	69	56	.552	150	4.77	736	5	1	2	1067.0	1,160	566	602	197	153	25	55	16	4,453	28	6.21	4.81	1.66	16.5	3.4	1.23	.288	5.08	114	4.64	112	9.78	-57
3	Dan Quisenberry D. Quisenberry	1.40	674	56	46	.549	0	2.76	379	0	0	244	1043.1	1,064	320	356	59	162	7	553	70	4,247	4	3.27	2.34	0.51	8.9	3.8	1.18	.276	3.07	69	3.23	82	9.18	81.6
4	Bob Tewksbury B. Tewksbury	1.45	302	110	102	.519	277	3.92	812	31	7	1	1807.0	2,043	787	884	142	292	41	8	22	7,623	24	4.04	2.78	0.71	10.7	3.8	1.29	.300	4.40	95	3.64	89	10.18	89.8
5	Kevin Slowey K. Slowey	1.51	137	43	36	.544	106	4.62	495	3	2	0	662.0	765	340	354	99	111	22	7	3	2,828	11	6.73	4.46	1.35	17.5	3.9	1.32	.317	4.81	112	4.15	102	10.40	-6.5
6	Josh Towers J. Towers	1.51	139	45	55	.450	112	4.95	389	4	2	1	731.1	887	402	441	122	123	35	14	13	3,158	6	4.79	3.16	1.50	12.3	3.9	1.38	.307	5.43	110	4.82	107	10.92	-26
7	Ken Raffensberger K. Raffensberger	1.56	150	54	65	.454	128	3.62	313	59	16	6	919.0	965	370	417	106	159	10	16		3,824	4	3.07	1.97	1.04	8.2	4.2	1.22	.265	4.08	89	3.87	94	9.45	23.9
8	Ryan Gusto R. Gusto	1.59	7	3	1	.750	3	2.78	23	0	0	0	22.2	21	7	7	2	4	0	0	0	90	0	9.13	5.75	0.79	25.6	4.4	1.10	.311	2.78	72	2.67	67	8.34	3.3
9	Robin Roberts R. Roberts	1.60	613	264	221	.544	558	3.40	2,178	285	42	21	4315.1	4,205	1,629	1,798	480	766	45	40	69	17,637	31	4.54	2.84	1.00	12.3	4.3	1.15	.263	3.75	89	3.49	91	8.77	169
10	Tomoyuki Sugano T. Sugano	1.61	5	2	1	.667	5	3.54	9	0	0	0	28.0	27	11	11	6	5	1	0	0	113	1	2.89	1.80	1.93	8.0	4.4	1.14	.228	3.54	92	5.81	148	8.68	-6
11	Fred Hutchinson F. Hutchinson	1.62	85	29	19	.604	47	3.78	140	19	3	2	467.0	522	196	222	34	84	8	24		1,965	6	2.70	1.67	0.66	7.1	4.3	1.30	.287	4.28	87	3.46	81	10.06	41.4
12	Spencer Schwellenbach S. Schwellenbach	1.62	26	9	8	.529	26	3.19	154	0	0	0	155.1	130	55	59	17	28	7	0	2	624	4	8.92	5.50	0.98	24.7	4.5	1.02	.270	3.42	77	3.25	82	7.53	12.2
13	Brad Radke B. Radke	1.63	378	148	139	.516	377	4.22	1,467	37	10	0	2451.0	2,643	1,150	1,233	326	445	62	0	12	10,244	28	5.39	3.30	1.20	14.3	4.3	1.26	.292	4.53	90	4.24	94	9.71	75.2
14	Bret Saberhagen B. Saberhagen	1.65	399	167	117	.588	371	3.34	1,715	76	16	1	2562.2	2,452	952	1,036	218	471	59	13	34	10,421	53	6.02	3.64	0.77	16.5	4.5	1.14	.281	3.64	80	3.26	80	8.61	225.4
15	Rick Reed R. Reed	1.66	273	93	76	.550	245	4.03	970	14	7	1	1545.2	1,601	692	748	213	285	44	6	28	6,407	11	5.65	3.40	1.24	15.1	4.4	1.22	.284	4.36	95	4.21	99	9.32	2.8
16	Carlos Silva C. Silva	1.73	316	70	70	.500	180	4.68	554	6	2	2	1241.2	1,496	645	687	153	238	45	39	25	5,319	32	4.02	2.33	1.11	10.4	4.5	1.40	.310	4.98	108	4.48	105	10.84	-32.9
17	Jon Lieber J. Lieber	1.73	401	131	124	.514	327	4.27	1,553	25	5	2	2198.0	2,388	1,043	1,158	285	422	49	18	52	9,300	30	6.36	3.68	1.17	16.7	4.5	1.28	.301	4.74	98	4.01	90	9.78	104.3
18	Fritz Peterson F. Peterson	1.73	355	133	131	.504	330	3.30	1,015	90	20	1	2218.1	2,217	813	947	173	426	42	9	75	9,103	33	4.12	2.38	0.70	11.2	4.7	1.19	.274	3.84	99	3.24	94	8.99	51.9
19	Shota Imanaga S. Imanaga	1.74	35	17	4	.810	35	2.82	201	0	0	0	207.1	173	65	79	34	40	3	0	0	832	3	8.73	5.03	1.48	24.2	4.8	1.03	.251	3.43	71	3.95	100	7.51	-0.1
20	Eric Hillman E. Hillman	1.75	49	4	14	.222	36	4.85	96	3	1	0	232.0	285	125	144	30	45	8	3	7	1,010	2	3.72	2.13	1.16	9.5	4.5	1.42	.307	5.59	125	4.49	115	11.06	-15
21	Miles Mikolas M. Mikolas	1.75	215	64	66	.492	187	4.19	808	3	2	0	1119.2	1,135	521	555	138	218	47	10	7	4,655	15	6.49	3.71	1.11	17.4	4.7	1.21	.289	4.46	103	4.04	99	9.12	2.7
22	Masahiro Tanaka M. Tanaka	1.78	174	78	46	.629	173	3.74	991	7	4	0	1054.1	983	438	476	159	208	26	0	1	4,299	32	8.46	4.76	1.36	23.1	4.8	1.13	.283	4.06	88	3.90	89	8.39	53.3
23	Greg Maddux G. Maddux	1.80	744	355	227	.610	740	3.16	3,371	109	35	0	5008.1	4,726	1,756	1,981	353	999	137	3	177	20,421	70	6.06	3.37	0.63	16.5	4.9	1.14	.281	3.56	76	3.25	78	8.49	519.5
24	Juan Marichal J. Marichal	1.82	471	243	142	.631	457	2.89	2,303	244	52	2	3507.0	3,153	1,126	1,329	320	709	40	11	82	14,236	51	5.91	3.25	0.82	16.2	5.0	1.10	.261	3.41	81	3.04	88	8.09	154.8
25	Lew Burdette L. Burdette	1.84	626	203	144	.585	373	3.66	1,074	158	33	32	3067.1	3,186	1,246	1,400	289	628	56	128	63	12,745	23	3.15	1.71	0.85	8.4	4.9	1.24	.271	4.11	101	3.68	103	9.35	-41.7