Former US Open champion Juan Martin del Potro overcame extreme heat and humidity in New York to defeat home hope John Isner and reach the semi-finals.
The 2009 champion capped off the day session in soaring temperatures by ousting 11th-seeded Isner in a heavyweight slugfest of the towering big-servers 6-7 (5-7) 6-3 7-6 (7-4) 6-2.
Del Potro, seeded third, dropped his first set of the tournament in an opening set tie-break, but rallied to make it eight wins in 12 meetings against Isner with another destructive display of power hitting.
"I'm so happy to reach another semi-final in my favourite tournament that's very special to me," said Del Potro.
"Of course beating John in this kind of match is like an epic. We both were tired in the end, we both fought until the end and I think I survived with my serve. That was the only difference I think."
Isner, who was looking to become the first American man to reach the semi-finals since Andy Roddick in 2006, relied on his huge accurate serve as temperatures of 34 degrees Celsius and intense humidity on Arthur Ashe Stadium began to take its toll, although he did enough to send the third into a tie-break.
Del Potro, who recorded a straight-sets victory over the 33-year-old in the fourth round of the French Open earlier this year, took control to take it and turn the match in his favour as both players invoked the 10-minute heat break rule before the start of the fourth.
A wobbly Isner was suffering badly from fatigue in between points but was determined to put on a gutsy performance.
But it was the giant Argentine who carried on from where he left off with a double break to see out the contest in style after three hours and 31 minutes as he marched into his third US Open semi-final.
Del Potro will now face defending champion and No 1 seed Rafael Nadal for a place in Sunday's final.
Nadal beat Del Potro in the semi-finals last year at Flushing Meadows, and again this year in the semi-finals of the French Open.
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Tennis is back on Sky Sports screens with the Laver Cup in September while we will also have coverage of the ATP Finals in November with every match live on Sky Sports. But first, we will be across the final major of the year in New York as the US Open right through to the final with live blogs, reports, features and reaction.