23. Bob Pettit (22.59 PER)
Long before my time (and probably your time too), Bob Pettit was roaming the paint as a dominating 6-foot-9 power forward for the Milwaukee/St. Louis Hawks. He played 11 seasons in the NBA and was the first player to win the MVP award during the 1956 season. Interestingly, Pettit was the first player to score 20,000 points and would go on to make the Naismith Memorial Basketball Hall of Fame. Pettit only missed the postseason twice in his career and would go on to win one NBA Championship.
Over the course of his 88 career postseason games, Pettit averaged 26 points, 15 rebounds, and three assists per game on 42 percent shooting from the field. During the late 50s and early 60s, Pettit was not only one of the most dominant big men in the game but also one of the most efficient players.
When naming some of the best big men in the game, Pettit is often a name that gets left out. However, when calculating the most efficient players in NBA playoff history, he checks in at No. 23.