Jaime Navarro has the worst career ERA when pitching at least 100 innings versus the Mariners, with an ERA of 6.08.

Interpreted as:

worst era by a player against mariners min 100 ip

	NAME	ERA	IP	G	W	L	W%	GS	SO	CG	SHO	SV	H	ER	R	HR	BB	HBP	GF	IBB	TBF	WP	K/9	BB/9	K/BB	HR/9	K%	BB%	WHIP	BABIP	RA	H/9
1	Jaime Navarro J. Navarro	6.08	117.0	23	5	12	.294	17	56	3	2	1	155	79	84	18	43	3	3	3	537	10	4.31	3.31	1.30	1.38	10.4	8.0	1.69	.329	6.46	11.92
2	Bruce Hurst B. Hurst	5.55	107.0	19	6	6	.500	17	78	3	0	0	119	66	73	17	43	2	0	2	479	3	6.56	3.62	1.81	1.43	16.3	9.0	1.51	.301	6.14	10.01
3	Richard Dotson R. Dotson	5.30	113.2	19	7	9	.438	19	57	2	1	0	126	67	71	18	43	5	0	1	503	2	4.51	3.40	1.33	1.43	11.3	8.5	1.49	.284	5.62	9.98
4	Jim Abbott J. Abbott	5.25	121.2	19	4	13	.235	19	63	2	0	0	154	71	86	12	39	0	0	4	554	1	4.66	2.88	1.62	0.89	11.4	7.0	1.59	.323	6.36	11.39
5	Bobby Witt B. Witt	5.16	136.0	23	5	9	.357	22	127	0	0	0	155	78	85	19	68	1	0	7	625	8	8.40	4.50	1.87	1.26	20.3	10.9	1.64	.332	5.63	10.26
6	Brad Radke B. Radke	5.06	154.2	24	7	11	.389	24	102	1	0	0	174	87	93	28	36	4	0	1	661	1	5.94	2.09	2.83	1.63	15.4	5.4	1.36	.297	5.41	10.13
7	Charles Nagy C. Nagy	4.98	157.1	25	8	12	.400	24	100	5	0	0	183	87	94	20	63	4	0	6	698	4	5.72	3.60	1.59	1.14	14.3	9.0	1.56	.319	5.38	10.47
8	Kevin Millwood K. Millwood	4.91	148.1	24	8	13	.381	24	90	1	0	0	184	81	91	19	37	5	0	2	660	3	5.46	2.24	2.43	1.15	13.6	5.6	1.49	.324	5.52	11.16
9	Darren Oliver D. Oliver	4.87	116.1	52	2	6	.250	13	84	0	0	0	116	63	70	17	55	4	8	5	513	7	6.50	4.26	1.53	1.32	16.4	10.7	1.47	.280	5.42	8.97
10	Scott Erickson S. Erickson	4.86	170.1	28	11	11	.500	27	97	3	1	0	192	92	106	19	69	10	1	2	755	6	5.13	3.65	1.41	1.00	12.8	9.1	1.53	.309	5.60	10.14
11	Kelvim Escobar K. Escobar	4.86	116.2	29	5	9	.357	16	89	2	0	3	139	63	76	14	36	5	8	2	519	8	6.87	2.78	2.47	1.08	17.1	6.9	1.50	.333	5.86	10.72
12	Jimmy Key J. Key	4.79	186.0	38	13	9	.591	30	109	2	1	0	203	99	104	25	58	1	1	1	795	5	5.27	2.81	1.88	1.21	13.7	7.3	1.40	.296	5.03	9.82
13	Mark Langston M. Langston	4.77	122.2	19	5	8	.385	19	93	2	0	0	128	65	67	13	48	5	0	0	526	5	6.82	3.52	1.94	0.95	17.7	9.1	1.43	.313	4.92	9.39
14	Jarrod Washburn J. Washburn	4.64	139.2	25	8	8	.500	22	75	1	0	0	143	72	73	17	49	4	0	2	599	3	4.83	3.16	1.53	1.10	12.5	8.2	1.37	.278	4.70	9.21
15	Andrew Heaney A. Heaney	4.63	122.1	25	4	10	.286	22	130	0	0	0	124	63	65	25	38	7	0	1	530	2	9.56	2.80	3.42	1.84	24.5	7.2	1.32	.300	4.78	9.12
16	Kenny Rogers K. Rogers	4.58	204.1	54	11	13	.458	30	100	1	1	1	225	104	121	23	81	10	9	5	910	10	4.40	3.57	1.23	1.01	11.0	8.9	1.50	.290	5.33	9.91
17	Kirk McCaskill K. McCaskill	4.57	165.1	42	11	13	.458	23	87	2	2	1	159	84	95	19	66	3	10	2	701	5	4.74	3.59	1.32	1.03	12.4	9.4	1.36	.266	5.17	8.66
18	Teddy Higuera T. Higuera	4.54	125.0	21	6	9	.400	21	99	2	0	0	121	63	74	13	36	5	0	0	530	1	7.13	2.59	2.75	0.94	18.7	6.8	1.26	.286	5.33	8.71
19	Tom Candiotti T. Candiotti	4.48	132.2	21	7	7	.500	20	91	3	0	0	143	66	74	17	42	2	0	0	570	8	6.17	2.85	2.17	1.15	16.0	7.4	1.39	.301	5.02	9.70
20	James Shields J. Shields	4.48	130.2	20	5	9	.357	20	120	1	0	0	131	65	71	24	40	2	0	0	555	6	8.27	2.76	3.00	1.65	21.6	7.2	1.31	.290	4.89	9.02
21	David Wells D. Wells	4.47	207.1	44	11	11	.500	29	132	3	0	1	210	103	112	34	49	2	4	3	870	6	5.73	2.13	2.69	1.48	15.2	5.6	1.25	.270	4.86	9.12
22	Storm Davis S. Davis	4.47	139.0	32	14	7	.667	19	81	5	1	1	149	69	74	14	53	1	4	4	602	8	5.24	3.43	1.53	0.91	13.5	8.8	1.45	.298	4.79	9.65
23	Charlie Leibrandt C. Leibrandt	4.44	117.2	20	5	7	.417	19	71	1	0	0	135	58	67	11	29	3	0	0	513	6	5.43	2.22	2.45	0.84	13.8	5.7	1.39	.311	5.12	10.33
24	Alex Fernandez A. Fernandez	4.40	102.1	16	7	3	.700	16	69	0	0	0	109	50	52	12	42	3	0	3	453	4	6.07	3.69	1.64	1.06	15.2	9.3	1.48	.297	4.57	9.59
25	Mike Smithson M. Smithson	4.38	135.2	21	8	10	.444	20	89	4	2	0	134	66	70	17	35	8	0	3	580	9	5.90	2.32	2.54	1.13	15.3	6.0	1.25	.271	4.64	8.89