Palmer appeared in the postseason eight times and was a vital member of three World Series Champions, six AL pennant winners and seven Eastern Division titleholders. He is the only pitcher in history to earn a win in a World Series game in three different decades. He is also the youngest to pitch a complete-game shutout in a World Series, doing so nine days before his 21st birthday in 1966, in which he defeated Sandy Koufax in Koufax's last appearance. He was one of the starters on the last rotation to feature four 20-game winners in a single season in 1971. He was elected to the Baseball Hall of Fame in 1990.