Phil Niekro, the first master of the knuckleball, died overnight at the age of 81, the Baseball Hall of Fame and Museum announced on Sunday.
No official cause of death was released.
“Phil Niekro’s record on the field ranks him as one of the game’s finest pitchers,” Jane Forbes Clark, chairman of the National Baseball Hall of Fame and Museum, said in an official statement. “As a mentor, leader and friend, Phil brought out the best in all of us in Cooperstown."
Niekro's career spanned more than two decades and saw the knuckleball specialist make five All-Star teams and win more than 300 games.