Milwaukee, owner of the worst record in the NBA, won for eighth time in 41 tries this season. The Bucks' latest losing streak ended at nine games.
After Knight's shot produced the final score, Detroit missed its final four field goal attempts. The last of those was a 3-point try at the buzzer by Rodney Stuckey.
Caron Butler had 30 points to lead Milwaukee and Knight added 16 points and nine assists.
Brandon Jennings had 30 points for the Pistons, who have lost three out of four, and Stuckey scored 23.