Alexander Zverev survives another US Open marathon as Auger-Aliassime crashes out

Just two days after spending four hours and 53 minutes on court to beat Lorenzo Sonego in his opening match, Zverev needed another four hours and 33 minutes to finally shake off the determined Frenchman, with his match only finishing at 2:15 a.m.

Zverev made the stronger start and edged the opening set, but Halys repeatedly refused to let the match slip away. The Frenchman levelled the contest in the second before the pair traded tight tie-breaks in the third and fourth sets.

Zverev eventually found a way through in the deciding set, breaking clear when it mattered most before closing out another physically demanding victory.

Zverev is also competing as the top seed at a major for the first time, adding another layer to his challenge.

His next test will be 25th seed Alejandro Tabilo, a familiar opponent at the US Open after Zverev beat the Chilean in the first round in New York last year.

Elsewhere, Felix Auger-Aliassime's US Open campaign came to a low-key end in the second round as he struggled physically during his defeat to Karen Khachanov.

The Canadian has had a good season as he reached the quarter-finals at both the French Open and Wimbledon, earning him the third seed status at the season-ending Grand Slam.

Having reached the semi-finals 12 months ago at Flushing Meadows, many tipped him to do even better this year, but that won't be the case as he suffered a 7-6 (7-5), 3-6, 2-6, 2-6 defeat to Khachanov.

After a good start, Auger-Aliassime started to feel ill in the second set, and his condition just never improved.

"I mean it's tough to talk about anything else than how I felt physically after a set and a half I just couldn't yeah couldn't ⦠[didn't] feel well and was dizzy and seeing spots and yeah, couldn't recover," he explained.

"I thought maybe it would pass, but it didn't. So that's the end of the tournament for me and now back to the drawing board."

When asked if he was feeling sick before the match, he replied: "No. I've never felt quite like that. I've had cramps before I felt, you know, tired towards the end of matches, but in a normal way.

"This was abnormal a little bit and there were no signs in the last couple of days and no signs this morning as well. So yeah, I'm not sure. I'm going to run some tests and see what comes out of it."

READ MORE: Coco Gauff defeats Badosa to reach US Open third round