Retooling before the 1956–57 season, the Hawks acquired Ed Macauley and rookie Cliff Hagan from the Boston Celtics for the draft rights to Bill Russell. The team added guard Slater Martin in an early-season deal with the New York Knicks while Alex Hannum arrived a few weeks later after being released by the Fort Wayne Pistons. Hannum became the team's third coach that season by taking over as player-coach with 31 games left on the schedule. Though they posted a 34-38 record in 1956–57, a series of tie-breaking playoff games against the Pistons and a three-game sweep of the Minneapolis Lakers had them in the NBA Finals. In Game 1 of the 1957 NBA Finals at the Boston Garden, Pettit scored 37 points as the Hawks shocked the Bill Russell-led Boston Celtics in double overtime. Pettit won his team the third game in the series with a late basket in St. Louis. His two free throws with six seconds left in Game 7 forced overtime, but Pettit's 39 points and 19 rebounds in 56 minutes weren't enough to win a double-overtime game. Pettit averaged 29.8 points and 16.8 rebounds per game during their 1957 playoff run.