The Pittsburgh Alleghenys had their worst record in a season in 1890, with a record of 23-113.

Interpreted as:

pirates worst record in a regular season all-time

	TEAM	REC	SEASON	W%	G	W	L	AB	R	H	2B	3B	HR	RBI	BB	HBP	SO	SB	CS	PA	TB	XBH	SH	SF	IBB	GIDP	AVG	OBP	SLG	OPS
1	Alleghenys	23-113	1890	.169	138	23	113	4,739	597	1,088	160	43	20	426	408	66	460	208		5,213	1,394	223					.230	.300	.294	.594
2	Pirates	42-112	1952	.273	155	42	112	5,193	515	1,201	181	30	92	478	486	26	724	43	41	5,775	1,718	303	70			104	.231	.300	.331	.631
3	Alleghenys	30-78	1884	.278	110	30	78	3,689	406	777	105	50	2		143	41	411			3,873	988	157					.211	.248	.268	.516
4	Alleghenys	31-67	1883	.316	98	31	67	3,607	525	892	120	58	13		164		345			3,771	1,167	191					.247		.324
5	Pirates	19-41	2020	.317	60	19	41	1,932	219	425	76	6	59	210	167	11	521	16	11	2,132	690	141	7	15	6	34	.220	.284	.357	.641
6	Pirates	50-104	1953	.325	154	50	104	5,253	622	1,297	178	49	99	571	524	36	715	41	39	5,902	1,870	326	89			117	.247	.319	.356	.675
7	Pirates	51-103	1917	.331	157	51	103	5,169	464	1,230	160	61	9	396	399	46	580	150		5,788	1,539	230	174				.238	.298	.298	.596
8	Pirates	53-101	1954	.344	154	53	101	5,088	557	1,260	181	57	76	526	566	25	737	21	13	5,836	1,783	314	99	58		125	.248	.323	.350	.673
9	Pirates	57-105	2010	.352	162	57	105	5,386	587	1,303	276	27	126	570	463	33	1,207	87	36	5,973	2,011	429	58	33	28	119	.242	.304	.373	.678
10	Pirates	57-104	1985	.354	161	57	104	5,436	568	1,340	251	28	80	535	514	14	842	110	60	6,099	1,887	359	91	44	64	131	.247	.311	.347	.658
11	Pirates	57-96	1950	.373	154	57	96	5,327	681	1,404	227	59	138	634	564	31	693	43		5,976	2,163	424	54			142	.264	.338	.406	.744
12	Pirates	61-101	2021	.377	162	61	101	5,336	609	1,261	240	35	124	570	529	49	1,328	60	30	5,982	1,943	399	31	37	24	102	.236	.309	.364	.673
13	Pirates	62-100	2022	.383	162	62	100	5,331	591	1,186	221	29	158	555	476	54	1,497	89	32	5,912	1,939	408	19	32	14	96	.222	.291	.364	.655
14	Pirates	62-100	2001	.383	162	62	100	5,398	657	1,333	256	25	161	618	467	67	1,106	93	73	6,027	2,122	442	60	35	51	114	.247	.313	.393	.706
15	Pirates	62-99	2009	.385	161	62	99	5,417	636	1,364	289	34	125	612	499	46	1,142	90	32	6,058	2,096	448	60	36	44	124	.252	.318	.387	.705
16	Pirates	60-94	1955	.390	154	60	94	5,173	560	1,262	210	60	91	532	471	21	652	22	22	5,790	1,865	361	93	32	64	132	.244	.308	.361	.668
17	Pirates	64-98	1986	.395	162	64	98	5,456	663	1,366	273	33	111	618	569	20	929	152	84	6,157	2,038	417	68	44	55	132	.250	.321	.374	.695
18	Pirates	62-92	1957	.403	155	62	92	5,402	586	1,447	231	60	92	551	374	23	733	46	35	5,942	2,074	383	97	46	40	107	.268	.315	.384	.699
19	Pirates	62-92	1947	.403	156	62	92	5,307	744	1,385	216	44	156	699	606	24	684	30		6,007	2,157	416	70			136	.261	.339	.406	.746
20	Pirates	58-86	1995	.403	144	58	86	4,937	629	1,281	245	27	125	587	456	24	972	84	55	5,501	1,955	397	51	33	45	88	.259	.323	.396	.719
21	Pirates	55-80	1891	.407	137	55	80	4,794	679	1,148	148	71	29	524	427	50	503	205		5,271	1,525	248					.239	.308	.318	.626
22	Pirates	63-91	1946	.409	155	63	91	5,199	552	1,300	202	52	60	508	592	15	555	48		5,907	1,786	314	101			125	.250	.328	.344	.672
23	Pirates	67-95	2008	.414	162	67	95	5,628	735	1,454	314	21	153	705	474	59	1,039	57	19	6,278	2,269	488	66	51	40	111	.258	.320	.403	.723
24	Pirates	67-95	2006	.414	162	67	95	5,558	691	1,462	286	17	141	656	459	89	1,200	68	23	6,217	2,205	444	62	49	49	153	.263	.327	.397	.723
25	Pirates	67-95	2005	.414	162	67	95	5,573	680	1,445	292	38	139	656	471	72	1,092	73	30	6,221	2,230	469	56	49	38	130	.259	.322	.400	.723