The Boston Red Sox had the most runs by a team in a loss in 1920, with 13 runs against the Tigers on September 17, 1920.

Interpreted as:

most runs by a team in a regular-season loss in 1920

	TEAM	R	L	DATE	TM		OPP	RESULT	W	L%	AB	H	2B	3B	HR	RBI	BB	HBP	SO	SB	CS	PA	TB	XBH	SH	AVG	OBP	SLG	OPS
1	Red Sox	13	1	9/17/1920	BSA	@	DET	L 13-14	0	1.000	44	9	3	1	0	4	18	0	4	0	0	64	14	4	2	.205	.435	.318	.754
2	Senators	11	1	9/21/1920	WSH	@	DET	L 11-12	0	1.000	37	16	3	1	1	11	5	1	1	1	1	44	24	5	1	.432	.512	.649	1.160
3	Cardinals	11	1	5/7/1920	SLN	vs	CIN	L 11-15	0	1.000	43	15	3	0	0	10	4	0	2	0	0	47	18	3	0	.349	.404	.419	.823
4	Braves	10	1	9/25/1920	BSN	@	PHN	L 10-12	0	1.000	43	17	3	0	3	10	0	0	1	1	0	44	29	6	1	.395	.395	.674	1.070
5	Reds	10	1	9/14/1920	CIN	@	PHN	L 10-21	0	1.000	42	16	4	1	0	8	3	1	2	0	0	48	22	5	2	.381	.435	.524	.959
6	Braves	10	1	8/10/1920	BSN	vs	CIN	L 10-13	0	1.000	38	13	3	1	0	10	4	1	2	1	0	44	18	4	1	.342	.419	.474	.892
7	Phillies	10	1	8/9/1920	PHN	vs	SLN	L 10-12	0	1.000	51	20	2	0	0	10	4	2	3	3	0	57	22	2	0	.392	.456	.431	.888
8	Browns	10	1	7/15/1920	SLA	@	NYY	L 10-13	0	1.000	47	18	4	1	3	9	3	0	4	5	0	51	33	8	1	.383	.420	.702	1.122
9	Indians	10	1	6/1/1920	CLE	vs	DET	L 10-11	0	1.000	39	16	4	1	0	10	7	0	1	0	0	50	22	5	4	.410	.500	.564	1.064
10	Tigers	10	1	4/20/1920	DET	@	CLE	L 10-11	0	1.000	34	9	1	0	0	8	12	0	4	0	0	47	10	1	1	.265	.457	.294	.751
11	Red Sox	9	1	9/24/1920	BSA	vs	PHA	L 9-10	0	1.000	37	11	3	1	0	7	5	1	1	1	0	43	16	4	0	.297	.395	.432	.828
12	Yankees	9	1	9/18/1920	NYY	@	CWS	L 9-15	0	1.000	40	11	3	0	0	8	3	0	5	0	0	43	14	3	0	.275	.326	.350	.676
13	Yankees	9	1	8/22/1920	NYY	vs	DET	L 9-11	0	1.000	37	10	1	1	0	9	7	0	8	0	0	45	13	2	1	.270	.386	.351	.738
14	Browns	9	1	8/17/1920	SLA	@	WSH	L 9-10	0	1.000	47	19	3	1	0	8	3	0	0	0	0	54	24	4	4	.404	.440	.511	.951
15	Phillies	9	1	8/11/1920	PHN	vs	SLN	L 9-18	0	1.000	39	14	4	0	1	9	0	1	4	0	0	41	21	5	1	.359	.375	.538	.913
16	Senators	9	1	7/2/1920	WSH	@	BSA	L 9-10	0	1.000	43	18	2	0	1	8	2	0	5	1	1	47	23	3	2	.419	.444	.535	.979
17	Indians	9	1	6/20/1920	CLE	vs	BSA	L 9-10	0	1.000	42	15	2	1	0	9	5	0	6	1	1	47	19	3	0	.357	.426	.452	.878
18	Athletics	9	1	6/17/1920	PHA	@	SLA	L 9-12	0	1.000	43	18	5	1	0	8	4	0	1	0	0	49	25	6	2	.419	.468	.581	1.049
19	Giants	9	1	6/1/1920	NYG	@	BKN	L 9-10	0	1.000	36	14	1	2	0	9	3	1	3	0	0	43	19	3	3	.389	.450	.528	.978
20	Reds	9	1	5/27/1920	CIN	@	SLN	L 9-16	0	1.000	40	13	4	2	0	7	4	0	5	1	0	44	21	6	0	.325	.386	.525	.911
21	Indians	9	1	5/26/1920	CLE	@	WSH	L 9-13	0	1.000	38	13	0	2	1	9	4	0	1	0	0	42	20	3	0	.342	.405	.526	.931
22	Senators	9	1	5/21/1920	WSH	vs	CWS	L 9-11	0	1.000	39	14	3	0	0	8	10	0	3	2	2	50	17	3	1	.359	.490	.436	.926
23	Browns	8	1	9/24/1920	SLA	@	DET	L 8-16	0	1.000	39	13	1	2	2	5	3	0	1	0	0	43	24	5	1	.333	.381	.615	.996
24	Athletics	8	1	9/17/1920	PHA	@	SLA	L 8-17	0	1.000	40	15	4	1	0	7	3	0	3	0	0	44	21	5	1	.375	.419	.525	.944
25	Cardinals	8	1	9/10/1920	SLN	@	BKN	L 8-9	0	1.000	44	12	0	2	2	7	3	0	9	0	1	47	22	4	0	.273	.319	.500	.819