U.S. Open: Jennifer Brady earns a shot at No. 1; Madison Keys wins a marathon

Reporting from New York —  Jennifer Brady had one overpowering thought after she lunged and fell to the ground on Court 17 during the third-set tiebreaker of her strenuous match against Romania’s Monica Niculescu on Saturday. “I didn’t want to get up,” said Brady, the former UCLA standout. “I was tired and laying there felt nice.”

After a few seconds’ respite she rose to her feet. Two points later, she had a 6-3, 4-6, 7-6 (3) victory and a berth in the fourth round of the U.S. Open. “Both fun and frustrating,” Brady said of the match, in which she showcased her devastating forehand.

Brady moved on to face world No. 1 Karolina Pliskova. Brady expects to feel awe and a sense of freedom because she has already acquitted herself so well. “At times you kind of come back to reality and are, ‘On paper, I’m not supposed to win this match,’ ” she said. “I’ll just go out there and compete and have fun.”

Naomi Osaka’s run ended in the third round when qualifier Kaia Kanepi of Estonia beat her, 6-3, 2-6, 7-5. “I think I was a bit emotionally unstable,” the 19-year-old Osaka said. “I think she would be more positive than negative. She didn’t have any outbursts or anything, and I had a lot.” French Open champion Jelena Ostapenko, weakened by a throat illness, fell to Daria Kasatkina 6-3, 6-2. “Many things came together, and because the draw was very open, I thought I can play better and better every match,” the 20-year-old Latvian said. “But today I was not feeling very well, so I couldn’t really play my game.”

Lucie Safarova advanced with a straight-sets win over Kurumi Nara and will face No. 20 CoCo Vandeweghe, who outbattled No. 10 Agnieszka Radwanska, 7-5, 4-6, 6-4. No. 4 Elina Svitolina moved on with a 6-4, 7-5 victory over American Shelby Rogers.

Among the men, 19-year-old Russian Andrey Rublev reached the fourth round with a 6-4, 6-4, 5-7, 6-4 decision over Damir Dzumhur of Bosnia-Herzegovina. Rublev will face No. 9 David Goffin, who was leading 7-5, 5-1 when No. 18 Gael Monfils retired. No. 6 Dominic Thiem, a straight-sets winner over Adrian Mannarino, will face No. 24 Juan Martin del Potro, who beat No. 11 Roberto Bautista Agut in straight sets.

Epic match

There seems to be at least one long, late, epic match played at the U.S. Open every year. The third-round encounter between No. 15 seed Madison Keys of the U.S. and No. 17 Elena Vesnina of Russia wins that honor for the first week of the tournament.

In the final match on Saturday’s schedule — which spilled over to 1:45 a.m. Eastern time Sunday — Keys held off Vesnina 2-6, 6-4, 6-1 under the closed roof at Arthur Ashe Stadium. Keys will face No. 4 Elina Svitolina in the fourth round. Keys was involved in a match last year that ended at 1:48 a.m., the latest ever for a U.S. Open women’s match.

Keys and Vesnina hugged at the net at the end of the match, a nice touch. A surprising number of fans remained to see the conclusion, maybe, in part, because the stadium offered a refuge from the rain.

The other matchups in the top half of the women’s draw: No. 1 Karolina Pliskova vs. Jennifer Brady; No. 20 CoCo Vandeweghe vs. Lucie Safarova, and Daria Kasatkina vs. qualifier Kaia Kanepi. In the top half: No. 9 Venus Williams vs. Carla Suarez Navarro; No. 3 Garbine Muguruza vs. No. 13 Petra Kvitova; No. 30 Julia Goerges vs. unseeded American Sloane Stephens, and No. 16 Anastasjia Sevastova vs. Maria Sharapova.

The men’s round of 16 matchups: No. 1 Rafael Nadal vs. Alexandr Dolgopolov; No. 9 David Goffin vs. Andrey Rublev; No. 3 Roger Federer vs. No. 33 Philipp Kohlschreiber; No. 6 Dominic Thiem vs. No. 24 Juan Martin del Potro; No. 17 Sam Querrey vs. No. 23 Mischa Zverev; No. 28 Kevin Anderson vs. Paolo Lorenzi; No. 12 Pablo Carrreno Busta vs. qualifier Denis Shapovalov; and No. 16 Lucas Pouille vs. No. 29 Diego Schwartzman.

Dolgopolov under scrutiny; Fognini suspended

Alexandr Dolgopolov of Ukraine said he has spoken to officials of the Tennis Integrity Unit, which is scrutinizing distinct shifts of betting patterns to heavily against him before his recent match in Winston-Salem, N.C. Dolgopolov lost badly to Thiago Monteiro. “I was the first one to come there and try to give them all the information so they can investigate it faster,” he said Saturday after his straight-sets victory over Viktor Troicki “They asked me about some information. They interviewed me. That’s it. That’s all I can do.”

A formal investigation has not begun.

The Grand Slam Board suspended Fabio Fognini of Italy from further participation here “pending a final determination whether a major offense has been committed during his first-round singles match,” the board said in a statement. The website ubitennis.net reported Fognini had verbally abused the umpire during that match and was fined $24,000 for three violations. He lost the singles match but had reached the third round in doubles.

helene.elliott@latimes.com

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