who had the best era as a rookie with a minimum of 100 ip

Tim Keefe has the lowest ERA by a rookie with 100.0+ innings pitched, with an ERA of 0.86 in 1880.

	NAME	ERA	IP	SEASON	TM	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	ERA-	FIP	FIP-	H/9	PRAA
1	Tim Keefe T. Keefe	0.86	105.0	1880	TRO	12	6	6	.500	12	39	12	0	0	68	10	27	0	16		0		397	1	3.34	1.37	2.44	0.00	9.8	4.0	0.80		2.31	35	2.25	91	5.83	3.6
2	Babe Adams B. Adams	1.11	130.0	1909	PIT	25	12	3	.800	12	65	7	3	2	88	16	25	0	23	3	11		475	1	4.50	1.59	2.83	0.00	13.7	4.8	0.85	.229	1.73	43	1.82	69	6.09	11.7
3	Denny Driscoll D. Driscoll	1.21	201.0	1882	PIT	23	13	9	.591	23	59	23	0	0	162	27	73	0	12		0		799	7	2.64	0.54	4.92	0.00	7.4	1.5	0.87		3.27	45	2.36	84	7.25	10.2
4	George Bradley G. Bradley	1.23	573.0	1876	STL	64	45	19	.703	64	103	63	16	0	470	78	229	3	38		0		2,269	34	1.62	0.60	2.71	0.05	4.5	1.7	0.89		3.60	58	2.14	101	7.38	-20.7
5	Guy Hecker G. Hecker	1.30	104.0	1882	LOU	13	6	6	.500	11	33	10	0	0	75	15	49	0	5		1		403	7	2.86	0.43	6.60	0.00	8.2	1.2	0.77		4.24	49	2.27	82	6.49	5.1
6	Harry Krause H. Krause	1.39	213.0	1909	PHA	32	18	8	.692	21	139	16	7	0	151	33	49	2	49	13	8		801	2	5.87	2.07	2.84	0.08	17.4	6.1	0.94	.249	2.07	58	1.91	82	6.38	9.5
7	Ed Reulbach E. Reulbach	1.42	291.2	1905	CHC	34	18	14	.563	29	152	28	5	1	208	46	71	1	73	18	5		1,124	5	4.69	2.25	2.08	0.03	13.5	6.5	0.96	.235	2.19	48	2.46	85	6.42	14
8	Jack Pfiester J. Pfiester	1.51	250.2	1906	CHC	31	20	8	.714	29	153	20	4	0	173	42	63	3	63	13	2		966	4	5.49	2.26	2.43	0.11	15.8	6.5	0.94	.232	2.26	57	2.21	80	6.21	15.4
9	John Ward J. Ward	1.51	334.0	1878	PRO	37	22	13	.629	37	116	37	6	0	308	56	151	3	34		0		1,365	26	3.13	0.92	3.41	0.08	8.5	2.5	1.02		4.07	68	2.26	101	8.30	-4.4
10	Bob Lee B. Lee	1.51	137.0	1964	LAA	64	6	5	.545	5	111	0	0	19	87	23	31	6	58	1	39	8	545	3	7.29	3.81	1.91	0.39	20.4	10.6	1.06	.220	2.04	44	2.85	79	5.72	11.4
11	George McQuillan G. McQuillan	1.53	359.2	1908	PHN	48	23	17	.575	42	114	32	7	2	263	61	88	1	91	6	6		1,367	5	2.85	2.28	1.25	0.03	8.3	6.7	0.98	.227	2.20	66	2.31	95	6.58	4.5
12	Steve Rogers S. Rogers	1.54	134.0	1973	MON	17	10	5	.667	17	64	7	3	0	93	23	28	5	49	1	0	3	527	3	4.30	3.29	1.31	0.34	12.1	9.3	1.06	.216	1.88	41	3.21	84	6.25	9.1
13	Jim Devlin J. Devlin	1.56	622.0	1876	LOU	68	30	35	.462	68	122	66	5	0	566	108	309	3	37		0		2,568	14	1.77	0.54	3.30	0.04	4.8	1.4	0.97		4.47	62	2.08	82	8.19	50.7
14	George Witt G. Witt	1.61	106.0	1958	PIT	18	9	2	.818	15	81	5	3	0	78	19	22	2	59	2	0	3	442	5	6.88	5.01	1.37	0.17	18.3	13.3	1.29	.255	1.87	42	2.92	76	6.62	11
15	Ed Summers E. Summers	1.64	301.0	1908	DET	40	24	12	.667	32	103	23	5	1	271	55	112	3	55	20	8		1,195	5	3.08	1.64	1.87	0.09	8.6	4.6	1.08	.264	3.35	66	2.29	99	8.10	2.4
16	Russ Ford R. Ford	1.65	299.2	1910	NYH	36	26	6	.813	33	209	29	8	1	194	55	69	4	70	8	3		1,112	5	6.28	2.10	2.99	0.12	18.8	6.3	0.88	.231	2.07	63	1.88	69	5.83	28.3
17	Frank Lange F. Lange	1.65	130.2	1910	CWS	23	9	4	.692	15	98	6	1	0	93	24	48	2	54	9	7		519	3	6.75	3.72	1.81	0.14	18.9	10.4	1.13	.256	3.31	68	2.47	99	6.41	-0.4
18	Otto Hess O. Hess	1.67	151.1	1904	CLE	21	8	7	.533	16	64	15	4	0	134	28	60	2	31	5	5		598	5	3.81	1.84	2.06	0.12	10.7	5.2	1.09	.266	3.57	65	2.46	99	7.97	0.3
19	Candy Cummings C. Cummings	1.67	216.0	1876	HAR	24	16	8	.667	24	26	24	5	0	215	40	97	0	14		0		913	7	1.08	0.58	1.86	0.00	2.8	1.5	1.06		4.04	69	2.19	90	8.96	9.4
20	Tommy Bond T. Bond	1.68	408.0	1876	HAR	45	31	13	.705	45	88	45	6	0	355	76	164	2	13		0		1,623	8	1.94	0.29	6.77	0.04	5.4	0.8	0.90		3.62	69	1.96	81	7.83	27.5
21	Jim McCormick J. McCormick	1.69	117.0	1878	IND	14	5	8	.385	14	36	12	1	0	128	22	47	0	15		0		490	4	2.77	1.15	2.40	0.00	7.3	3.1	1.22		3.62	80	2.31	109	9.85	-5.8
22	Bill Burns B. Burns	1.70	164.0	1908	WSH	23	6	11	.353	19	55	11	2	0	135	31	58	3	18	4	1		612	1	3.02	0.99	3.06	0.16	9.0	2.9	0.93	.248	3.18	74	2.07	96	7.41	0.7
23	Mark Eichhorn M. Eichhorn	1.72	157.0	1986	TOR	69	14	6	.700	0	166	0	0	10	105	30	32	8	45	7	38	14	612	2	9.52	2.58	3.69	0.46	27.1	7.4	0.96	.251	1.83	41	2.30	56	6.02	31.8
24	Henry Boyle H. Boyle	1.74	150.0	1884	SLU	19	15	3	.833	16	88	16	2	1	118	29	63	3	10		3		595	3	5.28	0.60	8.80	0.18	14.8	1.7	0.85		3.78	59	2.56	100	7.08	-1.1
25	Al Spalding A. Spalding	1.75	528.2	1876	CWS	61	47	12	.797	60	39	53	8	0	542	103	226	6	26		2		2,219	1	0.66	0.44	1.50	0.10	1.8	1.2	1.07		3.85	73	2.38	99	9.23	9