Alexander Zverev kept his bid for a second Grand Slam title alive with a straightforward win over Alejandro Tabilo, while Coco Gauff stayed strong to reach the fourth round of the US Open as several of her fellow Americans crashed out.

Naomi Osaka overcame a mental and physical battle to outlast Belgium’s Elise Mertens in a three-setter on Louis Armstrong Stadium on Saturday.

Two of the brightest young prospects in the women’s draw, and close friends off the court, put on a show as American Iva Jovic edged Filipina Alexandra Eala in a thrilling clash at Arthur Ashe Stadium.

After back-to-back five-setters, top seed Zverev finally enjoyed a quieter night as he overcame a small mid-match dip to see off Chile’s Tabilo 6-2, 7-6(2), 6-2.

“I think today was definitely much better than the last couple of days. I think I improved a lot from the baseline,” Zverev said.

“I wasn’t happy with the second set. I think, especially at the end of the second set, I lost focus a little bit. I was not moving as well. I was not playing as well. But I think the first and third sets are a big improvement to the other days. I’ll try to focus on that.”

Japanese 13th seed Osaka, a two-time US Open champion, worked through a challenge after letting slip a one-set and break advantage before managing an Achilles niggle to beat Mertens 6-3, 3-6, 7-5.

The match was as much a test of Osaka’s composure as her tennis, with the 28-year-old showing visible frustration before regaining control in the decider.

“Honestly, I didn’t feel like I played amazing, and it was really getting me down, like I was very negative on myself, so I’m really sorry about my behaviour,” an emotional Osaka said.

Jovic, 18, and Eala, 21, traded momentum throughout a contest that lasted more than three hours before the American prevailed 7-5, 3-6, 7-5. Jovic, the 14th seed, will next face compatriot and fan favourite Gauff.

Fourth seed Gauff had earlier provided the day’s clearest positive for the home fans, the 22-year-old beating Spain’s Cristina Bucsa 6-3, 6-4, as the 2023 champion looks to win a third Grand Slam crown.

Second seed Elena Rybakina continued her quest for a third major title and the top spot in the WTA rankings, advancing after a 7-6(6), 6-3 win over Yuliia Starodubtseva.

Australian Open champion Rybakina avenged the second-round defeat she suffered to the Ukrainian at the French Open. The Kazakh will face Osaka for a place in the quarterfinals.

Iga Swiatek, the 2022 champion, beat Marie Bouzkova 7-6(3), 7-6(3), while French Open champion Mirra Andreeva advanced by downing Nikola Bartunkova 6-2, 7-6(5).

Americans take a hit

The day had begun with a string of painful exits for the home players.

Past US Open finalists Taylor Fritz, Madison Keys and Amanda Anisimova crashed out in the third round, dealing a stinging blow to the home fans at Flushing Meadows.

Ninth seed Fritz had yet to drop a set in New York and looked on his way to another routine victory before Argentinian Francisco Cerundolo flipped the script and won 3-6, 4-6, 6-3, 6-4, 6-4.

It was the earliest exit in four years for the 2024 runner-up, and Cerundolo will next face Belgium’s Alexander Blockx, who shocked fifth seed Flavio Cobolli 6-7(4), 6-3, 6-0, 6-3.

The American women fared no better, as China’s Zheng Qinwen came back from a 5-0 deficit in the decider to beat 2017 runner-up Keys 1-6 7-6(3) 7-5 on the Grandstand, collapsing on the court in utter joy as she fought back from a career slump.

The Olympic champion reached the quarterfinals for the second straight time only two years ago but was forced to go through qualifying this time after a chronic right elbow injury derailed her career progress.

Last year’s runner-up and 10th seed Anisimova was unable to reverse her fortunes in a frustrating year at the majors, with a 6-2, 7-5 defeat by Anastasia Potapova.

Young American wildcard Michael Zheng was another casualty, unable to complete a comeback against Frenchman Arthur Gea in a 7-6(7), 3-6, 4-6, 6-3, 6-2 defeat. Gea became just the second lucky loser to reach the fourth round, after fellow countryman Corentin Moutet in 2022.

The day ended on a positive note for the home crowd, who spurred Learner Tien to a gritty 6-3, 1-6, 6-7(2), 6-3, 6-4 win over Czech Jakub Mensik.