The 53rd-ranked 19-year-old dispatched Belgian ninth seed David Goffin 7-5, 7-6 (7/5), 6-3 Monday to book a last-eight date Wednesday with 15-time Grand Slam champion and world number one Nadal. And he was pushed to two five-set matches in the first two rounds, which can't be good for a sore back and a 36-year-old body. And not simply because Federer owns a record 19 Grand Slam men's singles titles, five at the U.S. Open; Nadal ranks second overall with 15, two in NY.
If Federer beats del Potro and Nadal gets past Russia's Andrey Rublev in their quarterfinal matches, the top-seeded Nadal and third-seeded Federer would face off in the semifinals.
"I play one of the epic matches of my career here in the U.S. Open, which is my favorite tournament, in front of a great crowd", del Potro said afterwards.
Federer faces Del Potro for the first time in NY since the Argentine star rallied from a set and a break down to shock him in the 2009 final.
"Then I saw the crowd waiting for more tennis, waiting for my good forehands, good serves", he said.
Del Potro, and in all probability Nadal, still stand in his way of reaching the final, but if he maintains the play that accounted for Kohlschreiber in straight sets then he should be on one side of the net when the men's final takes place on Sunday. "I was ready to win the match in that moment".
With heart beyond words, del Potro fought through illness to come back from two sets down and beat young Dominic Thiem.
Pliskova needed to get back to the final to remain atop the WTA rankings.
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It was a third straight break as the world number five benefitted from Keys' unforced errors , eventually leveling the scoreline. David: Coco needs to work on her temper, as flashes of hot-headness marred a great performance against Radwanska in round 3.
The unseeded youngster set up the tie against Nadal in style, dropping only a single set in his journey to the last-eight encounter with the tournament's top seed.
Rublev´s run caps an impressive season by rising stars like Canadian teen Denis Shapovalov, into the US Open last 16, and German fourth seed Alexander Zverev, a five-time victor this year - both born to Russian parents in other nations.
They've split their four meetings, all of which were straight-set matches.
"This has been an emotional year for me".
Joining her was CoCo Vandeweghe, who ousted 20th-seeded Lucie Safarova of the Czech Republic 6-4, 7-6 (2), at Arthur Ashe Stadium.
It also bolsters Rublev´s confidence as he prepares to test how deep he can go in a Grand Slam event.
Rublev battled gamely to cling on through six break points at 3-1 down in the third, but for the third time in the match he eventually succumbed with a double fault on a break point, tossing his racquet away in disgust.
"I don't know how I was able to win that match", he said to ESPN afterward.
Nadal advanced to the quarterfinals at the U.S. Open for the first time since 2013 by rolling to a 6-2, 6-4, 6-1 victory over Alexandr Dolgopolov of Ukraine. "When I was on tennis court, I like it so much", Rublev said.