The Reds defeat the Cardinals, 12 – 6. St. Louis rookie C Keith McDonald homers in the 2nd inning, becoming only the second person in major league history to hit home runs in each of his first two big league at bats. Bob Nieman, in 1951, is the other. McDonald walks his third time up.

On July 6, 2000, The Reds defeat the Cardinals, 12 – 6. St. Louis rookie C Keith McDonald homers in the 2nd inning, becoming only the second person in major league history to hit home runs in each of his first two big league at bats. Bob Nieman, in 1951, is the other. McDonald walks his third time up.

Source:

Baseball Reference July 6