World No. 9 Naomi Osaka survived a scare against Ukrainian Marta Kostyuk, ranked No. 137 in the world, winning 6-3, 6-7(4), 6-2 to progress to the round of 16 of the U.S. Open on Friday.

The three-set match lasted two hours and 33 minutes due in part to two medical timeouts from Kostyuk, who pushed Osaka to the limit and showed no mercy to the two-time Grand Slam winner, who is carrying a hamstring injury.

Naomi Osaka of Japan serves the ball during her Women's Singles third round match against Marta Kostyuk of the Ukraine on Day Five of the 2020 US Open at USTA Billie Jean King National Tennis Center on Sept. 4, 2020, in the Queens borough of New York City. (Getty/Kyodo)

Osaka wore heavy strapping on the left hamstring she injured at last week's Western and Southern Open while she wore a mask bearing the name of Ahmaud Arbery, an unarmed black man who was shot dead while out jogging in Georgia in February.

After losing the second set tiebreak to the promising 18-year-old, Osaka lost her temper and flung her racket in frustration.

"While I was playing, honestly, I was cursing myself out so you wouldn't want to know what I was saying," Osaka said during an on-court interview.

In the decider, the real difference between the two was Kostyuk's failure to take her many opportunities to break while racking up her unforced error count -- 51 by the end of the match.

The fourth-seeded Osaka turned it around in the third set against Kostyuk, who was playing in her U.S. Open debut, saving five break points to get to 2-all, then from there won the last five games to close out the victory at Flushing Meadows.

"I'm very tired right now," the 2018 U.S. Open champion said.

"I just want to go to an ice bath. I'm not sure if this is classified as an emergency but I feel like I'm going to pass out."

Osaka will play 14th seed Anett Kontaveit next.


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