Alexander Zverev powers through as Van de Zandschulp escapes in US Open epic

Zverev, who was pushed to five sets in each of his opening two matches in New York, produced a far more comfortable performance against the 21st seed, winning 6-2, 6-2, 7-6 (7-3) in two hours and 30 minutes on Arthur Ashe Stadium.

The German made a fast start and never allowed Darderi to settle, breaking the Italian's serve twice in each of the opening two sets to establish a commanding lead. Darderi offered more resistance in the third, forcing a tie-break, but Zverev maintained his composure to close out the match in straight sets.

The victory was a welcome change of pace for Zverev after his first two matches had stretched deep into the night, with both marathon encounters finishing in the early hours of the morning.

"I don't know what to do with myself because it's before midnight," Zverev joked.

"I might go back to the practice court, I might go to a bar - that was a joke, unfortunately.

"Compared to the first two matches, the level has been going up."

Zverev will now turn his attention to the quarter-finals where he will meet Botic van de Zandschulp, who came through an extraordinary five-set clash with Frenchman Arthur Gea.

Gea came within one point of becoming the first lucky loser to reach a Grand Slam quarter-final, but ultimately suffered a heartbreaking defeat as Van de Zandschulp emerged victorious.

The 21-year-old failed to convert a match point in the third-set tie-break before being unable to serve out the fourth set, as Van de Zandschulp fought back from the brink to win 3-6 6-7 (0-7) 7-6 (9-7) 7-6 (7-3) 6-4 after five hours and 13 minutes.

The victory was the fourth-longest match in US Open history, with Van de Zandschulp admitting he had "no clue" how he completed the comeback.

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