NEW YORK — Alexander Zverev was two points from a first-round humiliation at Flushing Meadows. Instead, the No. 1 seed clawed his way out of a two-sets-to-one hole to outlast a rejuvenated Lorenzo Sonego 6-4, 3-6, 6-7(7), 7-5, 6-4 in a match that didn't finish until 1:55 a.m. Wednesday — by his own account the longest first-round battle of his career.

Seeded No. 1 at a Grand Slam for the first time, the German was serving at 4-5, 30/30 in the fourth set with Sonego two points from the finish line. A Zverev double fault had already handed the Italian the third-set tiebreak minutes earlier, and the 31-year-old from Turin looked ready to author one of the biggest opening-round shocks of the tournament. Zverev held that game, broke back, and rode the momentum to a 7-5 fourth set before closing it out in the fifth for a four-hour, 53-minute escape, according to a Yahoo Sports recap of the match.

Had he lost, Zverev would have become the first men's No. 1 seed eliminated in the opening round of a major since 2003 — a stat that has been circulating through tennis coverage all morning, per Tennis365's report on the aftermath.

"The Longest First Round I've Ever Played"

Zverev didn't dress it up afterward, calling it simply a fight for survival rather than a showcase of his best tennis.

"I'm just happy I won, that's it. Incredible battle, a lot of ups and downs — nearly five hours for a first round, I think it's the longest first-round match I ever played."

It's the second-longest Grand Slam match of Zverev's career overall, trailing only his five-hour, 27-minute Australian Open semifinal loss to Carlos Alcaraz earlier this year — meaning two of the three longest matches of his life have now come in the space of eight months. He credited Sonego, who has battled injuries and form dips for much of the season, with pushing him to the brink. ESPN's writeup noted the German missed more backhands than usual across the marathon.

The win keeps alive the top seed's bid for a maiden US Open title, but it comes at a cost: a body that logged nearly five hours of night-session tennis with the second round looming fast. Zverev next faces Frenchman Quentin Halys, against whom he holds a 2-0 career head-to-head, in a match that will now be scheduled with considerably less recovery time than he'd have liked.

For Sonego, the loss ends his run at Flushing Meadows, but a two-sets-to-one lead over the tournament's top seed will do plenty to quiet questions about his form heading into the fall swing.