The first game I remember going to was when I was 8 years old in 1971. It was the Padres hosting the Pirates. The only thing I remember about it is that it was bat night and I remember the incredible noise generated when all the kids would hit the bats like jackhammers on the concrete floors of San Diego Stadium. Yes, they gave away full-size 32 inch wooden bats to something like the first 15,000 kids 15 and younger.
To this day, I don't even know if Roberto Clemente played in the game, as I haven't been able to pin down an actual date for the game
The earliest games I can remember actual game action from would be from 1974, when I was 11.
Steve