Jerry Koosman, the left-handed pitcher who was a vital part of the New York Mets' 1969 World Series victory, has died. He was 83 years old.

The team announced his death on Sunday morning. According to Jay Horwitz, Koosman had been battling multiple illnesses and passed away surrounded by family in Osceola, Wisconsin.

Koosman was instrumental in the Mets' historic championship run. He earned the win in Game 2 of the 1969 World Series against the Baltimore Orioles, helping the team rebound after losing the opener. He also secured the victory in the decisive Game 5 to clinch the title for the Mets.

During his 12 seasons with the Mets, Koosman, a two-time All-Star, posted a 3.09 earned run average. His No. 36 jersey has been retired by the team. He also played for the Minnesota Twins, Chicago White Sox, and Philadelphia Phillies during his major league career.