Alexander Zverev has put a slow start to his US Open campaign further behind him as the top-seeded German defeated Italian Luciano Darderi 6-2 6-2 7-6(3) on Monday and moved into the quarter-finals.
Playing his fourth straight night-session match and having endured two-five-setters along the way, the 29-year-old was in no mood to hang around and powered through the first set after absorbing some late pressure on his otherwise solid serve.
After a misplaced drop shot from 21st seed Darderi gifted Zverev a second break in the next set, the French Open champion took full advantage to rack up a 4-0 lead that provided the perfect platform to double his advantage in the match.
Zverev suddenly lost momentum and was tested a lot more in the third set by Darderi's powerful first serve and drop shots, but he regrouped late on to prevail and become the only man to reach the quarter-finals at all four Grand Slams this year.
He will take on Dutchman Botic van de Zandschulp for a place in the semi-finals.

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