Allan Travers has allowed the most runs in a loss, with 24 runs against the Philadelphia Athletics on May 18, 1912.

Interpreted as:

pitcher with most runs allowed per regular-season loss

	NAME	R	L	DATE	TM		OPP	DEC	W	L%	GS	ERA	SO	CG	SHO	SV	IP	H	ER	HR	BB	HBP	GF	TBF	WP
1	Allan Travers A. Travers	24	1	5/18/1912	DET	@	PHA	L	0	1.000	1		1	1	0	0	8.0	26		0	7	0	0	52	0
2	Jack Katoll J. Katoll	23	1	9/2/1902	BAL	@	CLE	L	0	1.000	1	9.00	0	1	0	0	8.0	23	8	1	3	0	0	56	0
3	George Leclair G. Leclair	21	1	8/16/1914	PTF	@	IND	L	0	1.000	1	22.50	0	1	0	0	8.0	24	20	0	8	0	0	51	0
4	Jack Bracken J. Bracken	21	1	9/15/1901	CLE	@	DET	L	0	1.000	1	20.57	1	1	0	0	7.0	24	16	1	3	2	0	49	1
5	Doc Parker D. Parker	21	1	6/21/1901	CIN	@	BKN	L	0	1.000	1	15.75	0	1	0	0	8.0	26	14	1	2	0	0	51	1
6	Roy Patterson R. Patterson	21	1	5/5/1901	CWS	@	MIL	L	0	1.000	1	14.00	2	1	0	0	9.0	25	14	1	2	0	0	57	0
7	Tom Sheehan T. Sheehan	20	1	9/29/1915	PHA	@	WSH	L	0	1.000	1	13.50	3	1	0	0	8.0	23	12	0	4	1	0	52	0
8	Bob Groom B. Groom	20	1	5/11/1911	WSH	@	CWS	L	0	1.000	1		4	1	0	0	8.0	21		1	2	2	0	51	1
9	Al Orth A. Orth	19	1	5/7/1903	WSH	@	PHA	L	0	1.000	1	11.25	3	1	0	0	8.0	22	10	2	4	0	0	53	1
10	Bill Phillips B. Phillips	19	1	6/24/1901	CIN	@	PHN	L	0	1.000	1	11.25	4	1	0	0	8.0	22	10	1	4	0	0	54	1
11	Cy Falkenberg C. Falkenberg	18	1	8/16/1910	CLE	vs	PHA	L	0	1.000	1		5	1	0	0	9.0	23		0	2	0	0	50	1
12	Burt Keeley B. Keeley	18	1	8/8/1908	WSH	@	DET	L	0	1.000	1		5	1	0	0	8.0	22		0	3	0	0	49	2
13	Archie Stimmel A. Stimmel	18	1	9/23/1901	CIN	vs	BKN	L	0	1.000	1	12.60	1	0	0	0	5.0	20	7	2	1	0	0		0
14	Hod Lisenbee H. Lisenbee	17	1	9/11/1936	PHA	@	CWS	L	0	1.000	1	15.75	1	1	0	0	8.0	26	14	2	4	0	0	51	1
15	Howard Ehmke H. Ehmke	17	1	9/28/1923	BSA	vs	NYY	L	0	1.000	1	24.00	6	0	0	0	6.0	21	16	2	4	0	0	42	0
16	Ed Lafitte E. Lafitte	17	1	10/8/1911	DET	@	SLA	L	0	1.000	1		2	1	0	0	8.0	21		0	1	0	0	47	1
17	Bill Duggleby B. Duggleby	17	1	9/19/1903	PHN	@	CIN	L	0	1.000	1		2	1	0	0	8.0	19		0	4	0	0	46	0
18	Mike O'Neill M. O'Neill	17	1	5/31/1903	SLN	@	CHC	L	0	1.000	1		3	1	0	0	8.0	17		0	3	0	0	46	0
19	Jack Harper J. Harper	17	1	6/30/1902	SLA	vs	CLE	L	0	1.000	1	13.00	4	1	0	0	9.0	13	13	3	9	0	0	50	0
20	Pete Dowling P. Dowling	17	1	8/12/1901	CLE	vs	CWS	L	0	1.000	1	13.00	1	1	0	0	9.0	18	13	0	5	2	0	50	0
21	Casey Patten C. Patten	17	1	7/24/1901	WSH	@	CWS	L	0	1.000	1	16.88	1	1	0	0	8.0	20	15	0	4	0	0	52	0
22	Roscoe Miller R. Miller	17	1	6/24/1901	DET	@	BAL	L	0	1.000	1	15.75	0	1	0	0	8.0	22	14	0	3	2	0	50	0
23	Chubby Dean C. Dean	16	1	9/28/1940	PHA	@	BSA	L	0	1.000	1	15.75	1	1	0	0	8.0	19	14	1	5	0	0	47	2
24	Flint Rhem F. Rhem	16	1	8/4/1933	PHN	vs	NYG	L	0	1.000	1	16.88	1	0	0	0	8.0	21	15	0	3	1	0	47	0
25	Hugh McQuillan H. McQuillan	16	1	9/11/1927	BSN	@	CIN	L	0	1.000	1	20.25	2	0	0	0	6.2	17	15	1	3	0	0	39	0