Since 1999, Nate Cornejo has the worst K/9 in a season, with 2.13 per nine innings in 2003.

Interpreted as:

lowest single season k/9 with a minimum of 1 IP per team game by a player since 1999

	NAME	K/9	SEASON	TM	G	W	L	W%	GS	ERA	SO	CG	SHO	SV	IP	H	ER	R	HR	BB	HBP	GF	IBB	TBF	WP	BB/9	K/BB	HR/9	K%	BB%	WHIP	BABIP	RA	ERA-	FIP	FIP-	H/9	PRAA
1	Nate Cornejo N. Cornejo	2.13	2003	DET	32	6	17	.261	32	4.67	46	2	0	0	194.2	236	101	111	18	58	3	0	8	842	1	2.68	0.79	0.83	5.5	6.9	1.51	.304	5.13	106	4.69	106	10.91	-6.2
2	Kirk Rueter K. Rueter	2.65	2004	SFG	33	9	12	.429	33	4.73	56	0	0	0	190.1	225	100	108	21	66	1	0	5	840	1	3.12	0.85	0.99	6.7	7.9	1.53	.293	5.11	111	4.94	117	10.64	-16.2
3	Chien-Ming Wang C. Wang	3.14	2006	NYY	34	19	6	.760	33	3.63	76	2	1	1	218.0	233	88	92	12	52	2	1	4	900	6	2.15	1.46	0.50	8.4	5.8	1.31	.292	3.80	80	3.90	86	9.62	14.9
4	Danny Graves D. Graves	3.20	2003	CIN	30	4	15	.211	26	5.33	60	2	1	2	169.0	204	100	108	30	41	7	3	6	741	2	2.18	1.46	1.60	8.1	5.5	1.45	.289	5.75	123	5.47	123	10.86	-18.2
5	Aaron Cook A. Cook	3.31	2007	COL	25	8	7	.533	25	4.12	61	2	0	0	166.0	178	76	87	15	44	6	0	6	698	0	2.39	1.39	0.81	8.7	6.3	1.34	.285	4.72	86	4.57	98	9.65	1.9
6	Livan Hernandez L. Hernandez	3.35	2008	TOT	31	13	11	.542	31	6.05	67	2	0	0	180.0	257	121	129	25	43	2	0	4	811	3	2.15	1.56	1.25	8.3	5.3	1.67	.344	6.45	139	4.93	116	12.85	-13.7
7	Kirk Rueter K. Rueter	3.36	2002	SFG	33	14	8	.636	33	3.23	76	0	0	0	203.2	204	73	83	22	54	1	0	7	846	3	2.39	1.41	0.97	9.0	6.4	1.27	.263	3.67	82	4.42	111	9.01	-10.9
8	Scott Karl S. Karl	3.37	1999	MIL	33	11	11	.500	33	4.78	74	0	0	0	197.2	246	105	121	21	69	8	0	4	885	4	3.14	1.07	0.96	8.4	7.8	1.59	.316	5.51	105	4.92	107	11.20	-6.8
9	Carlos Silva C. Silva	3.37	2004	MIN	33	14	8	.636	33	4.21	76	1	1	0	203.0	255	95	100	23	35	5	0	2	869	5	1.55	2.17	1.02	8.7	4.0	1.43	.318	4.43	91	4.36	99	11.31	0.4
10	Carlos Silva C. Silva	3.39	2005	MIN	27	9	8	.529	27	3.44	71	2	0	0	188.1	212	72	83	25	9	3	0	2	749	0	0.43	7.89	1.19	9.5	1.2	1.17	.292	3.97	80	4.17	100	10.13	0.1
11	Kirk Rueter K. Rueter	3.47	2000	SFG	32	11	9	.550	31	3.96	71	0	0	0	184.0	205	81	92	23	62	2	0	5	799	1	3.03	1.15	1.13	8.9	7.8	1.45	.284	4.50	89	5.02	112	10.03	-12.3
12	Carlos Silva C. Silva	3.49	2006	MIN	36	11	15	.423	31	5.94	70	0	0	0	180.1	246	119	130	38	32	7	2	4	811	1	1.60	2.19	1.90	8.6	3.9	1.54	.313	6.49	133	5.75	131	12.28	-28.6
13	Ismael Valdez I. Valdez	3.55	2004	TOT	34	14	9	.609	31	5.19	67	1	1	0	170.0	202	98	105	33	49	2	2	3	751	1	2.59	1.37	1.75	8.9	6.5	1.48	.282	5.56	129	5.68	134	10.69	-28.5
14	Horacio Ramirez H. Ramirez	3.56	2005	ATL	33	11	9	.550	32	4.63	80	1	1	0	202.1	214	104	108	31	67	2	0	4	847	4	2.98	1.19	1.38	9.4	7.9	1.39	.274	4.80	111	5.23	124	9.52	-23.5
15	Brian Meadows B. Meadows	3.62	2000	TOT	33	13	10	.565	32	5.13	79	2	0	0	196.1	234	112	119	32	64	8	0	6	869	3	2.93	1.23	1.47	9.1	7.4	1.52	.294	5.46	112	5.54	119	10.73	-19.9
16	Brian Meadows B. Meadows	3.63	1999	FLA	31	11	15	.423	31	5.60	72	0	0	0	178.1	214	111	117	31	57	5	0	5	795	4	2.88	1.26	1.56	9.1	7.2	1.52	.290	5.90	128	5.62	124	10.80	-22.3
17	Brad Penny B. Penny	3.67	2011	DET	31	11	11	.500	31	5.30	74	0	0	0	181.2	222	107	117	24	62	4	0	1	803	9	3.07	1.19	1.19	9.2	7.7	1.56	.310	5.80	127	5.01	124	11.00	-19.6
18	Omar Olivares O. Olivares	3.72	1999	TOT	32	15	11	.577	32	4.16	85	4	0	0	205.2	217	95	105	19	81	9	0	0	885	6	3.54	1.05	0.83	9.6	9.2	1.45	.287	4.59	85	4.81	99	9.50	1
19	Mike Hampton M. Hampton	3.73	2002	COL	30	7	15	.318	30	6.15	74	0	0	0	178.2	228	122	135	24	91	7	0	4	838	9	4.58	0.81	1.21	8.8	10.9	1.79	.318	6.80	127	5.52	122	11.49	-17.6
20	Brian Anderson B. Anderson	3.80	2004	KCR	35	6	12	.333	26	5.64	70	2	1	0	166.0	217	104	123	33	53	1	2	4	745	2	2.87	1.32	1.79	9.4	7.1	1.63	.313	6.67	116	5.76	125	11.77	-20.6
21	Henderson Alvarez III H. Alvarez III	3.80	2012	TOR	31	9	14	.391	31	4.85	79	1	1	0	187.1	216	101	110	29	54	3	0	2	807	3	2.59	1.46	1.39	9.8	6.7	1.44	.291	5.28	115	5.17	123	10.38	-19.4
22	Dennis Springer D. Springer	3.80	1999	FLA	38	6	16	.273	29	4.86	83	3	2	1	196.1	231	106	121	23	64	7	3	4	855	2	2.93	1.30	1.05	9.7	7.5	1.50	.307	5.55	111	4.89	108	10.59	-8.2
23	Kirk Rueter K. Rueter	3.82	2001	SFG	34	14	12	.538	34	4.42	83	0	0	0	195.1	213	96	105	25	66	4	0	4	840	1	3.04	1.26	1.15	9.9	7.9	1.43	.284	4.84	106	4.93	118	9.81	-17.7
24	John Lannan J. Lannan	3.88	2009	WSH	33	9	13	.409	33	3.88	89	2	1	0	206.1	210	89	100	22	68	6	0	5	875	3	2.97	1.31	0.96	10.2	7.8	1.35	.272	4.36	93	4.69	110	9.16	-9.4
25	Jimmy Anderson J. Anderson	3.88	2001	PIT	34	9	17	.346	34	5.10	89	1	0	0	206.1	232	117	123	15	83	11	0	14	922	6	3.62	1.07	0.65	9.7	9.0	1.53	.300	5.37	117	4.49	103	10.12	-3.3