Croatian Borna Coric saved six match points as he rallied from 5-1 down in the fourth set to stun Stefanos Tsitsipas 6-7(2) 6-4 4-6 7-5 7-6(4) and send the fourth seed tumbling out of the U.S Open in the third round on Friday.
In the sort of late drama that would on any other year have had the Flushing Meadows crowd baying for more, Coric staged a remarkable comeback at an empty Louis Armstrong Stadium to reach the fourth round after the fifth set tiebreak.
The gritty 27th seed had looked down for the count when Tsitsipas twice served for the match in the fourth set but the 22-year-old Greek faltered with victory in his grasp.
Coric again had to come from a break down in the fifth but looked indefatigable even after 4 1/2 hours on court and secured a famous victory on his second match point.
"I just have to be honest and have to say that I was real lucky," said Coric, who will face Australian Jordan Thompson on Sunday for a spot in his first Grand Slam quarter-final.
"At 5-4, I think he was 40-0 ... it was just pure luck. I just made some unbelievable returns and yeah, I was a bit lucky in the end."
Tsitsipas, who won the ATP Finals at the end of last season and has targeted a maiden Grand Slam title this year, showcased his athleticism and shot-making in bursts throughout the contest.
He might have been able to see off his opponent earlier had he been able to put sustained pressure on the Croatian's serve but looked to have the match in the bag when he broke to win the third set and then won five of the next six games.
"In the third and fourth sets he was playing unbelievable tennis and I felt I had absolutely no chance," said Coric, one of four players to test positive for COVID-19 after playing on the ill-fated Adria Tour earlier this year
"(After that) I played some unbelievable points and he also dropped his level a little bit."
Tsitsipas did not hold a news conference after the match due to the lateness of the hour but posted a single line on his Twitter feed.
"This is probably the saddest and funniest at the same time thing that has ever happened in my career!" the Athenian wrote.
(Reporting by Nick Mulvenney in Sydney; Editing by Peter Rutherford)
