Dellin Betances has the best K/9 for the Yankees in a season, with 14.04 per nine innings in 2015.

Interpreted as:

highest k/9 with a minimum of 0.5 IP per team game in a season by a yankee

	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	Dellin Betances D. Betances	14.04	2015	NYY	74	6	4	.600	0	1.50	131	0	0	9	84.0	45	14	17	6	40	3	17	2	332	9	4.29	3.28	0.64	39.5	12.0	1.01	.257	1.82	37	2.47	59	4.82	15.6
2	Dellin Betances D. Betances	13.50	2014	NYY	70	5	0	1.000	0	1.40	135	0	0	1	90.0	46	14	15	4	24	4	8	1	341	2	2.40	5.63	0.40	39.6	7.0	0.78	.241	1.50	36	1.64	42	4.60	22.2
3	Gerrit Cole G. Cole	12.06	2021	NYY	30	16	8	.667	30	3.23	243	2	1	0	181.1	151	65	69	24	41	2	0	0	726	5	2.03	5.93	1.19	33.5	5.6	1.06	.305	3.42	76	2.91	67	7.49	28.1
4	Gerrit Cole G. Cole	11.59	2020	NYY	12	7	3	.700	12	2.84	94	2	1	0	73.0	53	23	27	14	17	2	0	0	288	2	2.10	5.53	1.73	32.6	5.9	0.96	.242	3.33	65	3.88	87	6.53	4.9
5	Gerrit Cole G. Cole	11.53	2022	NYY	33	13	8	.619	33	3.50	257	0	0	0	200.2	154	78	81	33	50	2	0	0	793	2	2.24	5.14	1.48	32.4	6.3	1.02	.268	3.63	92	3.46	87	6.91	11.5
6	James Paxton J. Paxton	11.11	2019	NYY	29	15	6	.714	29	3.82	186	0	0	0	150.2	138	64	71	23	55	2	0	0	633	7	3.29	3.38	1.37	29.4	8.7	1.28	.313	4.24	84	3.85	83	8.24	13.3
7	Luke Weaver L. Weaver	11.04	2024	NYY	62	7	3	.700	0	2.89	103	0	0	4	84.0	52	27	28	10	26	4	12	0	331	1	2.79	3.96	1.07	31.1	7.9	0.93	.223	3.00	72	3.33	79	5.57	8.1
8	Michael King M. King	10.92	2023	NYY	49	4	8	.333	9	2.75	127	0	0	6	104.2	88	32	35	10	32	5	10	1	431	2	2.75	3.97	0.86	29.5	7.4	1.15	.304	3.01	64	3.13	71	7.57	14.6
9	Mariano Rivera M. Rivera	10.87	1996	NYY	61	8	3	.727	0	2.09	130	0	0	5	107.2	73	25	25	1	34	2	14	3	425	1	2.84	3.82	0.08	30.6	8.0	0.99	.279	2.09	43	1.87	39	6.10	35.8
10	Domingo Germán D. Germán	10.72	2018	NYY	21	2	6	.250	14	5.57	102	0	0	0	85.2	81	53	55	15	33	5	2	0	375	7	3.47	3.09	1.58	27.2	8.8	1.33	.300	5.78	131	4.38	102	8.51	-0.6
11	Luis Severino L. Severino	10.71	2017	NYY	31	14	6	.700	31	2.98	230	0	0	0	193.1	150	64	73	21	51	6	0	0	783	6	2.37	4.51	0.98	29.4	6.5	1.04	.272	3.40	68	3.07	69	6.98	29.8
12	Chad Green C. Green	10.65	2021	NYY	67	10	7	.588	0	3.12	99	0	0	6	83.2	57	29	32	14	17	0	15	2	315	5	1.83	5.82	1.51	31.4	5.4	0.88	.232	3.44	74	3.58	83	6.13	6.8
13	Michael Pineda M. Pineda	10.61	2016	NYY	32	6	12	.333	32	4.82	207	0	0	0	175.2	184	94	98	27	53	6	0	1	756	7	2.72	3.91	1.38	27.4	7.0	1.35	.339	5.02	113	3.79	86	9.43	11.9
14	Joba Chamberlain J. Chamberlain	10.58	2008	NYY	42	4	3	.571	12	2.60	118	0	0	0	100.1	87	29	32	5	39	2	5	3	417	4	3.50	3.03	0.45	28.3	9.4	1.26	.324	2.87	60	2.65	61	7.80	18.6
15	Luis Severino L. Severino	10.35	2018	NYY	32	19	8	.704	32	3.39	220	1	1	0	191.1	173	72	76	19	46	5	0	0	780	8	2.16	4.78	0.89	28.2	5.9	1.14	.314	3.57	79	2.95	68	8.14	28.6
16	Will Warren W. Warren	10.30	2025	NYY	25	7	5	.583	25	4.34	140	0	0	0	122.1	113	59	61	14	54	2	0	0	532	2	3.97	2.59	1.03	26.3	10.2	1.37	.307	4.49	107	3.67	86	8.31	8.2
17	David Cone D. Cone	10.25	1997	NYY	29	12	6	.667	29	2.82	222	1	0	0	195.0	155	61	67	17	86	4	0	2	805	14	3.97	2.58	0.78	27.6	10.7	1.24	.290	3.09	64	3.34	75	7.15	24.9
18	Carlos Rodón C. Rodón	10.25	2025	NYY	24	11	7	.611	24	3.35	159	0	0	0	139.2	97	52	58	19	56	4	0	0	570	4	3.61	2.84	1.22	27.9	9.8	1.10	.235	3.74	83	3.88	91	6.25	6.3
19	Ron Davis R. Davis	10.23	1981	NYY	43	4	5	.444	0	2.71	83	0	0	6	73.0	47	22	22	6	25	0	22	3	285	1	3.08	3.32	0.74	29.1	8.8	0.99	.240	2.71	76	2.42	66	5.79	10.1
20	Luis Gil L. Gil	10.15	2024	NYY	29	15	7	.682	29	3.50	171	0	0	0	151.2	104	59	60	18	77	8	0	0	637	6	4.57	2.22	1.07	26.8	12.1	1.19	.237	3.56	87	4.13	98	6.17	1.5
21	Phil Hughes P. Hughes	10.05	2009	NYY	51	8	3	.727	7	3.03	96	0	0	3	86.0	68	29	31	8	28	5	6	1	351	4	2.93	3.43	0.84	27.4	8.0	1.12	.280	3.24	66	3.22	70	7.12	12.7
22	Carlos Rodón C. Rodón	10.03	2024	NYY	32	16	9	.640	32	3.96	195	0	0	0	175.0	157	77	81	31	57	10	0	0	736	3	2.93	3.42	1.59	26.5	7.7	1.22	.284	4.17	99	4.38	104	8.07	-3
23	Nestor Cortes N. Cortes	9.97	2021	NYY	22	2	3	.400	14	2.90	103	0	0	0	93.0	75	30	32	14	25	2	3	0	374	2	2.42	4.12	1.35	27.5	6.7	1.08	.265	3.10	69	3.78	87	7.26	5.6
24	Luis Severino L. Severino	9.88	2022	NYY	19	7	3	.700	19	3.18	112	0	0	0	102.0	72	36	37	14	30	4	0	0	405	1	2.65	3.73	1.24	27.7	7.4	1.00	.237	3.26	84	3.69	93	6.35	3.2
25	Rich Gossage R. Gossage	9.87	1982	NYY	56	4	5	.444	0	2.23	102	0	0	30	93.0	63	23	23	5	28	0	43	5	356	1	2.71	3.64	0.48	28.7	7.9	0.98	.262	2.23	56	2.12	53	6.10	19.7