Luis Castillo had the worst ERA with 182.0+ innings pitched in 2021, with an ERA of 3.98.

Interpreted as:

highest era by a player in 2021, min 182 ip

	NAME	ERA	IP	SEASON	TM	G	W	L	W%	GS	SO	CG	SHO	H	ER	R	HR	BB	HBP	IBB	TBF	WP	K/9	BB/9	K/BB	HR/9	K%	BB%	WHIP	BABIP	RA	ERA-	FIP	FIP-	H/9	PRAA
1	Luis Castillo L. Castillo	3.98	187.2	2021	CIN	33	8	16	.333	33	192	0	0	181	83	94	19	75	7	4	803	1	9.21	3.60	2.56	0.91	23.9	9.3	1.36	.318	4.51	90	3.74	84	8.68	14.5
2	Nathan Eovaldi N. Eovaldi	3.75	182.1	2021	BOS	32	11	9	.550	32	195	0	0	182	76	81	15	35	7	2	764	6	9.63	1.73	5.57	0.74	25.5	4.6	1.19	.326	4.00	82	2.78	64	8.98	30.9
3	Kyle Gibson K. Gibson	3.71	182.0	2021	TOT	31	10	9	.526	30	155	0	0	158	75	78	17	64	8	2	754	2	7.66	3.16	2.42	0.84	20.6	8.5	1.22	.276	3.86	86	3.86	88	7.81	10.3
4	José Berríos J. Berríos	3.52	192.0	2021	TOT	32	12	9	.571	32	204	1	0	159	75	83	22	45	15	0	781	3	9.56	2.11	4.53	1.03	26.1	5.8	1.06	.277	3.89	81	3.46	82	7.45	16.5
5	Frankie Montas Jr. F. Montas Jr.	3.37	187.0	2021	OAK	32	13	9	.591	32	207	0	0	164	70	79	20	57	7	1	778	11	9.96	2.74	3.63	0.96	26.6	7.3	1.18	.296	3.80	82	3.37	81	7.89	16.5
6	Charlie Morton C. Morton	3.34	185.2	2021	ATL	33	14	6	.700	33	216	0	0	136	69	77	16	58	17	1	756	5	10.47	2.81	3.72	0.78	28.6	7.7	1.04	.267	3.73	79	3.17	75	6.59	21.4
7	Sandy Alcantara S. Alcantara	3.19	205.2	2021	MIA	33	9	15	.375	33	201	1	0	171	73	85	21	50	10	2	837	6	8.80	2.19	4.02	0.92	24.0	6.0	1.07	.270	3.72	76	3.41	82	7.48	17.2
8	Adam Wainwright A. Wainwright	3.05	206.1	2021	STL	32	17	7	.708	32	174	3	1	168	70	72	21	50	9	3	828	4	7.59	2.18	3.48	0.92	21.0	6.0	1.06	.256	3.14	75	3.66	88	7.33	11.5
9	Julio Urías J. Urías	2.96	185.2	2021	LAD	32	20	3	.870	32	195	0	0	151	61	67	19	38	7	3	745	2	9.45	1.84	5.13	0.92	26.2	5.1	1.02	.272	3.25	73	3.12	73	7.32	23.8
10	Robbie Ray R. Ray	2.84	193.1	2021	TOR	32	13	7	.650	32	248	0	0	150	61	62	33	52	4	0	773	5	11.54	2.42	4.77	1.54	32.1	6.7	1.04	.268	2.89	63	3.68	87	6.98	11.8
11	Kevin Gausman K. Gausman	2.81	192.0	2021	SFG	33	14	6	.700	33	227	0	0	150	60	66	20	50	4	1	775	7	10.64	2.34	4.54	0.94	29.3	6.5	1.04	.274	3.09	70	3.00	74	7.03	23.5
12	Zack Wheeler Z. Wheeler	2.78	213.1	2021	PHI	32	14	10	.583	32	247	3	2	169	66	72	16	46	8	1	849	6	10.42	1.94	5.37	0.68	29.1	5.4	1.01	.288	3.04	66	2.58	60	7.13	40.7
13	Walker Buehler W. Buehler	2.47	207.2	2021	LAD	33	16	4	.800	33	212	0	0	149	57	61	19	52	6	2	815	5	9.19	2.25	4.08	0.82	26.0	6.4	0.97	.247	2.64	61	3.15	74	6.46	26