Novak Djokovic is on to the U.S. Open quarterfinals -- and potentially a showdown with Roger Federer.
Djokovic beat Joao Sosa 6-3, 6-4, 6-3 to move into the final eight at Flushing Meadows for the 11th time.
The opponent for the No. 6 seed could be the second-seeded Federer, who was to play Australian John Millman in a night match Monday.
Djokovic, the reigning Wimbledon champion, improved to 28-0 against players ranked outside the top 50 at the U.S. Open.
Earlier, 2014 runner-up Kei Nishikori beat Philipp Kohlschreiber 6-3, 6-2, 7-5 to reach the final eight in his second straight Grand Slam tournament.