The Cincinnati Reds retire the Number 24 jersey worn by Hall of Famer Tony Perez, making it just the sixth to be retired by the oldest professional baseball organization. The former first baseman joins Fred Hutchinson (1), Johnny Bench (5), Joe Morgan (8), Ted Kluszewski (18) and Frank Robinson (20) in this hallowed club. Ken Griffey, Jr., after being acquired by the Reds in the off-season, agrees to switch his uniform number from 24 to 30, the number worn by his father, Ken Griffey Sr., as a member of the Big Red Machine.

On May 27, 2000 — The Cincinnati Reds retire the Number 24 jersey worn by Hall of Famer Tony Perez, making it just the sixth to be retired by the oldest professional baseball organization. The former first baseman joins Fred Hutchinson (1), Johnny Bench (5), Joe Morgan (8), Ted Kluszewski (18) and Frank Robinson (20) in this hallowed club. Ken Griffey, Jr., after being acquired by the Reds in the off-season, agrees to switch his uniform number from 24 to 30, the number worn by his father, Ken Griffey Sr., as a member of the Big Red Machine.

Source:
Baseball Reference May 27