Jason Isringhausen (born September 7, 1972 in Brighton, Illinois) is a relief pitcher in Major League Baseball, and is currently the closer for the St. Louis Cardinals. He began his career as a starter but injuries forced him to miss most of the 1997 season as well as the entire 1998 season. When he was finally healthy in 1999, he was moved to the bullpen after only five starts.
Isringhausen has prospered since his move to the bullpen. He had a league-leading 47 saves in 2004, and had a career-best 2.14 ERA in 2005. Isringhausen started the 2006 season with two losses and a blown save in his first five appearances. However, "Izzy" leads the league with 18 saves, and his ERA is now 2.78. Following his second of three blown saves, he picked up his first win of the season.
For his career, Isringhausen is 37-38 with a 3.57 ERA and 234 saves. In his brief career as a starter he threw three complete games and one shutout.