which mlb team has the highest single season batting average since integration

The Boston Red Caps had a batting average of .266 in 1876.

	TEAM	AVG	SEASON	G	W%	W	L	AB	R	H	2B	3B	HR	RBI	BB	SO	PA	TB	XBH	SLG
1	Red Caps	.266	1876	70	.557	39	31	2,722	471	723	96	24	9	281	58	98	2,780	894	129	.328
2	White Stockings	.337	1876	66	.788	52	14	2,748	624	926	131	32	8	441	70	45	2,818	1,145	171	.417
3	Reds	.234	1876	65	.138	9	56	2,372	238	555	51	12	4	132	41	136	2,413	642	67	.271
4	Dark Blues	.267	1876	69	.691	47	21	2,664	429	711	96	22	2	265	39	78	2,703	857	120	.322
5	Grays	.249	1876	69	.455	30	36	2,570	280	641	68	14	6	191	24	98	2,594	755	88	.294
6	Mutuals	.227	1876	57	.375	21	35	2,180	260	494	39	15	2	161	18	35	2,198	569	56	.261
7	Athletics	.271	1876	60	.237	14	45	2,387	378	646	79	35	7	249	27	36	2,414	816	121	.342
8	Brown Stockings	.259	1876	64	.703	45	19	2,478	386	642	73	27	2	264	59	63	2,537	775	102	.313
9	Red Caps	.296	1877	61	.700	42	18	2,368	419	700	91	37	4	291	65	121	2,433	877	132	.370
10	White Stockings	.278	1877	60	.441	26	33	2,273	366	633	79	30	0	248	57	111	2,330	772	109	.340
11	Reds	.255	1877	58	.263	15	42	2,135	291	545	72	34	6	224	78	110	2,213	703	112	.329
12	Dark Blues	.270	1877	60	.534	31	27	2,358	341	637	63	31	4	201	30	97	2,388	774	98	.328
13	Grays	.280	1877	61	.583	35	25	2,355	339	659	75	36	9	248	58	140	2,413	833	120	.354
14	Brown Stockings	.244	1877	60	.467	28	32	2,178	284	531	51	36	1	198	57	147	2,235	657	88	.302
15	Red Caps	.241	1878	60	.683	41	19	2,220	298	535	75	25	2	194	35	154	2,255	666	102	.300
16	White Stockings	.290	1878	61	.500	30	30	2,333	371	677	91	20	3	284	88	157	2,421	817	114	.350
17	Reds	.276	1878	61	.617	37	23	2,281	333	629	67	22	5	228	58	141	2,339	755	94	.331
18	Blues	.236	1878	63	.400	24	36	2,300	293	542	76	15	3	197	64	197	2,364	657	94	.286
19	Grays	.250	1878	61	.250	15	45	2,212	256	552	65	20	2	177	69	214	2,281	663	87	.300
20	Grays	.263	1878	62	.550	33	27	2,298	353	604	107	30	8	251	50	218	2,348	795	145	.346
21	Red Caps	.274	1879	84	.643	54	30	3,217	562	883	138	51	20	393	90	222	3,307	1,183	209	.368
22	White Stockings	.259	1879	83	.582	46	33	3,116	437	808	167	32	3	293	73	294	3,189	1,048	202	.336
23	Reds	.264	1879	81	.538	43	37	3,085	485	813	127	53	8	364	66	207	3,151	1,070	188	.347
24	Grays	.296	1879	85	.702	59	25	3,392	612	1,003	142	55	12	405	91	172	3,483	1,291	209	.381
25	Bisons	.252	1879	79	.590	46	32	2,906	394	733	105	54	2	279	78	314	2,984	952	161	.328