Novak Djokovic and Juan Martin del Potro have advanced to the semifinals of the Western & Southern Open, setting up a rematch of the Olympic bronze-medal match.
Del Potro beat Djokovic for the bronze on Wimbledon's grass in London.
Del Potro defeated France's Jeremy Chardy 6-1, 6-3 in the opening match Friday. His biggest concern has been a sore left wrist that he'll have examined before the U.S. Open, which he won in 2009.
Djokovic knocked off Marin Cilic 6-3, 6-2, reaching a Masters semifinal for the second straight week. He won the Rogers Cup in Toronto last Sunday. Top-ranked Roger Federer was scheduled for the night match.
On the women's side, Serena and Venus Williams also had quarterfinal matches later on.