Juan Martin del Potro battled back from the brink of defeat to overcome Dominic Thiem in a five-set thriller and set up a blockbuster clash against Roger Federer.
The 2009 champion at Flushing Meadows came into his match against the sixth seed struggling with illness and subsequently dropped the opening two sets of the fourth-round match.
After taking the third set, he then trailed 5-2 in the fourth and looked down-and-out, but the 24th seed went on to save two match points with a couple of trademark aces before dominating the tie-break.
Both players were producing some outrageous hitting, but it was Del Potro who sealed the win when Thiem double-faulted to hand the giant Argentine an emotional 1-6 2-6 6-1 7-6 (7-1) 6-4 victory in three hours and 35 minutes.
“Oh my God,” Del Potro told the crowd. “I don’t know what can I say after this big battle. I was sick the last two days. I came here trying to play as well as I can.
“When I saw all of this crowd cheering for me, my illness cleared up. I was trying to feel better every game. I fight like this because of you guys.”
Del Potro will next face 19-time Grand Slam champion Roger Federer after the Swiss legend defeated German 33rd seed Philipp Kohlschreiber 6-4 6-2 7-5.
Del Potro defeated Federer in a five-set final eight years ago in the New York final for his only Grand Slam title, snapping his 40-match tournament win streak after dispatching Rafael Nadal in the semi-finals.
“Maybe I have the chance to play Roger again in this tournament, which is special for me,” Del Potro said, adding, “I would like to have the trophy after these matches.”
Asked what he might do to recover for his Wednesday battle for a semi-final berth, the South American replied, “I think it’s a nap for me.”
Federer reached his 12th quarter-final in New York after extending his winning streak over Kohlschreiber to 12-0 and is now an impressive 32-1 in Arthur Ashe Stadium night matches.
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