Defending champion Novak Djokovic saw off Gael Monfils in a bizarre match of fluctuating fortunes to reach his seventh US Open final in New York.
The Serb beat French 10th seed Monfils 6-3 6-2 3-6 6-2 and will face Stan Wawrinka or Kei Nishikori in the final.
Djokovic, 29, had treatment on both shoulders as both men struggled in punishing humidity.
More to follow.