NEW YORK (AFP) - Rafael Nadal stepped up his pursuit for a fourth US Open title with a 6-3, 3-6, 6-1, 6-2 win over 2014 champion Marin Cilic on Monday (Sept 2) to advance to the quarter-finals for a ninth time.
Second seed Nadal - the winner in New York in 2010, 2013 and 2017 - will meet Argentine 20th seed Diego Schwartzman for a place in the semi-finals.
Schwartzman upset sixth seed Alexander Zverev under the roof on a rainswept Labor Day at Arthur Ashe Stadium, winning 3-6, 6-2, 6-4, 6-3.
Germany's Zverev was enjoying his deepest run in New York but committed 17 double faults and 65 unforced errors and received a point penalty for swearing as Schwartzman advanced to a second US Open quarter-final in three years.
"Generally my season so far has not been the best," said Zverev, who has reached just two quarter-finals in 18 Grand Slam appearances. "Grand Slams were not actually worse than my season like they were last year and two years ago. I hope I can attack them next year."
He said he was hindered by a "very swollen" back and right hip following a fall in his previous match. "I had a lot of chances which I didn't use early in the match. He kind of ran away with it."
Zverev lost his serve three times during the second set but appeared to have steadied himself when he moved a break ahead at 3-2 in the third, only for Schwartzman to wrest the momentum back in his favour after a lengthy sixth game.
"It was tough because I was feeling I had the chance to win this and I had a few break points I could not take," Schwartzman, who was also a quarter-finalist at last year's French Open and matched his best Grand Slam run on Monday. "He was up a break and then I recovered really quickly and I felt great after that."