The 1965–66 season was both his most productive and noteworthy. He averaged a career-high 18.4 points and 3.6 rebounds per game as the Royals went 45-35 and, in the Eastern Division semifinals, extended the Boston Celtics to a fifth and deciding game before falling to the eventual NBA champions. On December 15 he scored a career-high 34 points against the Celtics, and followed that up on January 5 with another career-high of 35 points. During the season, Smith was selected to the 1966 NBA All-Star Game and, surprisingly for a game that including sixteen future Hall-of-Famers, Smith was named MVP after he scored 24 points in 26 minutes. It was his only All-Star appearance, and for winning the MVP award, he received a new Ford Galaxie car.