I remember him. He never was the #5 hitter (after Mays,McCovey) the Giants counted on. One sportswriter said he drinks too much. Back then the only black player who made the team were the best. No room for marginal types.
He played 11 seasons for the Giants. A 1966 All-Star, Hart was a career .278 hitter with 170 home runs and 578 RBIs in 1,125 games.
Hardly a “marginal” player