World number one Novak Djokovic won a punishing five-setter against Alexander Zverev to set up a US Open final against Daniil Medvedev and keep alive his bid for a calendar Grand Slam.
Russian second seed Medvedev had earlier kept alive his hopes of a first major title with a 6-4 7-5 6-2 win over Canadian Felix Auger-Aliassime.
Djokovic then recovered from falling a set behind to win 4-6 6-2 6-4 4-6 6-2.
Victory over Medvedev on Sunday at Flushing Meadows would move Djokovic clear of the 20 majors won by Roger Federer and Rafael Nadal.
History-chasing Djokovic would also become the first man to win all four majors in the same year since Rod Laver in 1969.
“There’s only one match left, all in, let’s do it. I’m going to put my heart and my soul and my body and my head into that one.
“I am going to treat the next match like it is the last match in my career,” Djokovic said.