The Latest: Osaka pushed to 3 sets at US Open by Kostyuk, 18

NEW YORK (AP) — The Latest on the U.S. Open tennis tournament (all times local):

2:10 p.m.

Naomi Osaka is headed to a third set in the U.S. Open’s third round.

The two-time Grand Slam champion took the opening set 6-3, but 18-year-old Marta Kostyuk, who is playing in just her second major tournament, grabbed the second in a tiebreaker.

When the second set ended with Osaka missing a backhand return, she flung her racket away.

Osaka won the U.S. Open in 2018 and the Australian Open the following year. She has been ranked No. 1 and is seeded fourth at Flushing Meadows.

Kostyuk is ranked 137th.

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12:45 p.m.

Petra Martic is the first player into the fourth round at this year’s U.S. Open.

The No. 8-seeded Martic made it that far at Flushing Meadows for the second year in a row, advancing Friday with a 6-3, 6-3 victory over Varvara Gracheva.

Gracheva simply made too many mistakes, with 33 unforced errors — three times as many as Martic.

As Gracheva’s deficit grew larger and larger, she knew more than anyone that it’s never over until it’s over: In the previous round, she trailed No. 30 Kristina Mladenovic 6-1, 5-1 and faced four match points before coming all the way back to win.

There was no such turnaround this time.

Martic now will try to get to the second Grand Slam quarterfinal of her career after reaching that stage at last year’s French Open.

She has lost her other six fourth-round matches at major tournaments, including against Serena Williams at the U.S. Open in 2019.

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11:10 a.m.

Play is underway in third-round matches on Day 5 at the U.S. Open.

Past champions Naomi Osaka and Novak Djokovic are among those scheduled to play in Arthur Ashe Stadium later Friday.

Osaka will face Marta Kostyuk to begin the day session in the tournament’s main arena.

The top-seeded Djokovic will bring a 28-match winning streak, including 25-0 this season, into his night match against Jan-Lennard Struff.

After rain Thursday night suspended play on the courts without a roof, the weather is much better — sunny with the temperature around 80 degrees Fahrenheit (a little above 25 Celsius).

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