Griffey would hit a double in his first at - bat .
Ken Griffey , Jr. made his major league baseball debut on April 3 , 1989 , in a game against the Oakland Athletics .
Ken Griffey , Jr. would hit a double in Ken Griffey , Jr. 's first at - bat .
Ken Griffey , Jr. made his major league baseball debut on April 3 , 1989 , in a game against the Oakland Athletics .