Knight was selected by the Detroit Pistons with the eighth overall pick in the 2011 NBA draft. In May 2012, he earned NBA All-Rookie First Team honors, becoming the first Pistons' rookie since Grant Hill (1994–95) to be named to the NBA All-Rookie First Team. Knight's 847 points were the second-most by a Pistons' rookie since the 1985–86 season and his 12.8 points per game was the fourth highest average by a Pistons' rookie since the 1980–81 season.