Doc Rivers has lost the most games by a coach in game sevens, with 10 losses.

COACH	L	GP	MPG	PPG	RPG	APG	SPG	BPG	TPG	FGM	FGA	FG%	3PM	3PA	3P%	FTM	FTA	FT%	MIN	PTS	REB	AST	STL	BLK	TOV	PF
Doc Rivers	10	16	240.0	93.9	40.0	20.4	7.4	5.6	12.5	34.5	78.6	43.9	6.8	22.4	30.2	18.2	23.1	78.6	3,840	1,503	640	326	119	90	200	359
Pat Riley	5	11	240.0	96.4	41.3	22.5	7.0	4.9	13.1	36.0	78.5	45.9	4.6	14.0	33.1	19.7	27.5	71.6	2,640	1,060	454	247	77	54	144	259
Gregg Popovich	4	7	243.6	97.9	42.4	18.3	6.7	5.3	11.1	34.6	78.6	44.0	8.1	21.3	38.3	20.6	24.9	82.8	1,705	685	297	128	47	37	78	147
George Karl	4	7	243.6	96.6	42.4	21.9	5.1	6.1	14.6	34.7	78.3	44.3	5.9	17.3	33.9	21.3	26.3	81.0	1,705	676	297	153	36	43	102	177
Rick Adelman	4	5	250.0	92.6	46.2	22.8	8.4	5.0	12.4	35.2	87.4	40.3	5.6	19.6	28.6	16.6	25.0	66.4	1,250	463	231	114	42	25	62	116
Larry Brown	4	10	242.5	93.7	41.4	22.1	7.3	4.5	11.1	35.8	81.6	43.9	4.2	11.8	35.8	18.3	25.2	72.6	2,425	937	414	221	73	45	111	234
Don Nelson	4	7	240.0	106.7	39.4	23.1	8.0	7.1	12.4	41.3	88.7	46.5	4.0	10.3	38.7	20.7	25.6	81.0	1,680	747	276	162	56	50	87	176
Erik Spoelstra	3	8	240.0	95.9	42.1	17.3	6.4	5.3	12.3	35.3	78.4	45.0	8.4	25.0	33.5	17.0	21.9	77.7	1,920	767	337	138	51	42	98	155
Mike Brown	3	4	240.0	87.3	41.0	16.3	5.5	5.5	11.3	30.3	79.3	38.2	7.8	26.3	29.5	19.0	28.0	67.9	960	349	164	65	22	22	45	99
Jeff Van Gundy	3	4	240.0	87.0	38.3	18.5	5.8	6.3	11.5	31.5	76.8	41.0	4.8	18.0	26.4	19.3	23.8	81.1	960	348	153	74	23	25	46	90
Phil Jackson	3	9	242.8	90.2	46.1	18.2	6.4	4.6	11.9	32.9	80.0	41.1	4.9	16.4	29.7	19.6	27.9	70.1	2,185	812	415	164	58	41	107	202
John MacLeod	3	4	240.0	98.5	42.5	21.8	9.0	6.5	15.8	39.0	84.8	46.0	1.5	7.5	20.0	19.8	27.0	73.1	960	394	170	87	36	26	63	97
Dick Motta	3	7	240.0	96.7	49.1	21.0				38.1	92.7	41.1				20.4	26.9	76.1	1,680	677	344	147				165
Fred Schaus	3	5	245.0	109.6	56.8					40.0	94.6	42.3				29.6	39.6	74.7	1,225	548	284					132
Billy Donovan	2	2	240.0	95.0	46.5	22.0	4.5	4.5	14.0	34.5	82.5	41.8	11.5	30.5	37.7	14.5	19.0	76.3	480	190	93	44	9	9	28	27
Mike Budenholzer	2	3	248.3	92.0	47.3	18.7	7.7	5.3	10.0	34.7	93.3	37.1	10.0	37.7	26.5	12.7	17.7	71.7	745	276	142	56	23	16	30	62
Frank Vogel	2	3	240.0	84.0	43.3	14.3	4.7	7.0	17.0	31.7	70.7	44.8	6.0	19.0	31.6	14.7	19.0	77.2	720	252	130	43	14	21	51	64
Lionel Hollins	2	2	240.0	81.0	41.5	12.5	8.5	4.5	11.5	30.0	82.5	36.4	2.5	14.0	17.9	18.5	25.0	74.0	480	162	83	25	17	9	23	40
Rick Carlisle	2	4	240.0	103.0	40.3	23.5	7.8	4.5	12.5	38.3	80.3	47.7	9.3	24.3	38.1	17.3	22.5	76.7	960	412	161	94	31	18	50	81
Mike Dunleavy	2	2	240.0	95.5	32.5	13.0	6.5	2.5	10.5	36.5	77.5	47.1	4.0	9.5	42.1	18.5	21.0	88.1	480	191	65	26	13	5	21	49
Paul Westphal	2	3	240.0	110.3	45.3	20.0	6.3	6.3	11.3	32.7	77.0	42.4	6.7	19.7	33.9	38.3	44.3	86.5	720	331	136	60	19	19	34	75
Chuck Daly	2	3	240.0	104.0	41.7	22.0	9.3	4.7	10.3	40.3	82.0	49.2	1.7	5.3	31.3	21.7	30.0	72.2	720	312	125	66	28	14	31	76
Billy Cunningham	2	4	240.0	104.3	40.8	26.3	7.3	9.5	17.5	40.0	82.8	48.3	0.3	0.7	50.0	24.0	30.5	78.7	960	417	163	105	29	38	70	109
Hubie Brown	2	2	240.0	99.0	34.5	21.0		2.5	10.0	38.5	82.5	46.7	0.0	3.0	0.0	22.0	25.5	86.3	480	198	69	42		5	20	51
Lenny Wilkens	2	5	240.0	104.0	45.8	23.2	7.0	8.2	14.4	40.0	84.6	47.3	2.3	8.3	28.0	22.6	30.2	74.8	1,200	520	229	116	35	41	72	120