The two time champion Novak Djokovic is into the US Open quarter-finals with a straight sets victory over Joao Sousa from Portugal 6-3 6-4 6-3. Next for Djokovic could be a mouth water encounter against Roger Federer if he can come through against Australian John Millman later today. The former number ones have not faced each other this early in a Grand Slam since the Australian Open in 2007. The defending champion Rafael Nadal moved into the last eight with a four sets win against world number 37 Nikoloz Basilashvili 6-3 6-3 6-7 6-4, to set up a thrilling clash with ninth seed Dominic Thiem.