Petkovic, who has played with bone spur problems in his right ankle this season, made 10-of-17 shots from the field and grabbed eight rebounds. It was Minnesota's first win since March 28 at Charlotte.
The Timberwolves' late-season slide has coincided with the absence of Kevin Love and his averages of 26 points and 13 rebounds a game. Love has been out for the last six contests after suffering a concussion.
The Pistons, who dropped their second straight and lost for the 40th time this year, were led by Tayshaun Prince with 18 points.
Susan Sarandon 'very excited' about daughter's pregnancy
Teacher apologizes for showing sexual image of herself in class