Tough test brings out frustration as Novak Djokovic reaches US Open last eight

Novak Djokovic ranted and raged but still found a way to win as the world number one booked his place in the US Open quarter-finals with a four-set victory over Spain’s Roberto Bautista Agut.

Djokovic furiously stamped on his bag and snapped a racket he was not even using after Bautista Agut clinched the second set, but the top seed recovered his composure to win 6-3 4-6 6-4 6-3.