Win

From BR Bullpen

Baseball rules credit a win to one pitcher on the victorious team. The pitcher receiving credit is normally the pitcher of record at the time that the team takes a lead that it never relinquishes. There are two rare exceptions to this general principle:

A starting pitcher must pitch for at least 5 innings to receive credit for a win, unless the game goes only 5 innings (in which case he must pitch at least 4) or he is pitching in an exhibition match (such as the All-Star Game) that has rules restricting the length of his appearance.
A reliever may be denied the victory if he is "ineffective in a brief appearance".

In either exceptional case, the official scorer is allowed to determine which subsequent relief pitcher deserves credit for the victory. In practice, most official scorers will credit the pitcher who immediately follows the one denied the victory.

A relief win is a win earned by a pitcher who did not start the game. This statistic is one of those used to determine the winner of the Rolaids Relief Award.

Records for Pitcher Wins
Span	Pitcher	Total	Notes
MLB Career	Cy Young	511
MLB Season	Charley Radbourn	59	1884
MLB Season (since 1900)	Jack Chesbro	41	1904
NPB Career	Masaichi Kaneda	400
NPB Season	Victor Starfin	42	1939
NPB Season	Kazuhisa Inao	42	1961
Negro Leagues Career	Bullet Joe Rogan	151
Negro Leagues Season	Nip Winters	27	1924
Minor Leagues Career	Bill Thomas	384
Minor Leagues Season	Stoney McGlynn	41	1906
Cuban National League Career	Pedro Luis Lazo	247
Korea Baseball Organization Career	Jin-woo Song	201	through 2006
Korea Baseball Organization Season	Myeong-bu Chang	30	1983
Serie A1 Season	Giuseppe Silva	21	1970
AAGPBL Career	Helen Nicol	163
AAGPBL Season	Joanne Winter	33	1946
AAGPBL Season	Connie Wisniewski	33	1946