NEW YORK - Crowd-pleaser Coco Gauff came through a tough battle with qualifier Timea Babos 6-2 4-6 6-4 on Thursday to set up a third-round clash at the U.S. Open against top seed and defending champion Naomi Osaka.

The 15-year-old American phenom was forced to dig deep to become the youngest player since Anna Kournikova in 1996 to reach the third round of the women’s singles at Flushing Meadows.

“I was tested a lot. I think we both were just testing each other,” Gauff said. “It’s just that type of match where anyone could have won.”

Gauff rode into this year’s tournament with enormous expectations after a dream run at Wimbledon where she beat five-time champion Venus Williams on her way to the fourth round.

On Thursday, the two players were evenly matched for most of the contest, with Gauff maintaining a slightly tighter performance and committing 34 unforced errors compared to 42 from Hungarian Babos.

It was another comeback for Gauff, who worked her way back from a one-set deficit in her first-round match, and the young upstart showed off her fighting instincts after failing to fend off a critical break point late in the second set.

“I thought that the first set, I definitely was in control. In the second set, she raised her level and I wasn’t able to finish the set,” Gauff said.

A fired-up Gauff prevailed after a 12-stroke rally late in the third set to set up a break point opportunity, pumping her fists wildly and shouting in excitement in front of a packed crowd that was firmly on her side.

“I couldn’t even see any empty seats!” Gauff said of the crowd, which included retired NBA star Kobe Bryant.

“I don’t even know how to really thank you guys. I’m super honored to be American and play in New York City.”

Gauff will face off against 21-year-old Osaka, who also holds the Australian Open title, in the third round of the tournament on Saturday in a clash that may provide a glimpse at the future of the women’s game.

“Obviously she’s an amazing player,” said Gauff. “She’s defending champion. She’s won two slams. She’s No. 1. She’s only 21.

“We’re both pretty young. But I’m a little bit newer to the game. So I’m just curious to see how my game matches up against her.”

Djokovic nurses shoulder injury

Novak Djokovic will look to keep a recent shoulder injury at bay as he resumes his U.S. Open title defense in the third round, while Serena Williams will look to take another step closer to a record-tying 24th Grand Slam title on Friday.

Djokovic will conclude the evening session inside Arthur Ashe Stadium when he faces American Denis Kudla in a rematch of their second-round Wimbledon meeting, which the Serbian won in straight sets.

But top-seeded Djokovic, who has won four of the last five Grand Slams, may need his left shoulder to cooperate as sudden pain in his second-round match affected his serve and backhand and nearly ended his title defense.

“Good thing about Grand Slams is you have a day off in between the matches,” said Djokovic. “I’m hoping that with a proper medical help and treatments, I’ll be able to get myself in a better state.”

Federer looks to set pace early

Roger Federer will try to avoid another slow start when he kicks off the day session on Arthur Ashe against Briton Dan Evans and will be followed on the court by six-time champion Williams.

Federer has lost the opening set in each of his first two matches before flipping a switch and cruising to the finish line in dominant fashion.

The 20-time Grand Slam champion, who improved to 2-0 all-time against Evans when he beat him in the second round of the Australian Open this year, is not losing any sleep over his sluggish starts.

“I don’t think there is per se a secret to a good start other than warming up well, being well prepared mentally. Not underestimating your opponent ... You know me, I will always do that,” said Federer.

“So when it happens like this back-to-back matches, you know, it’s just a bit frustrating more than anything ... but, yeah, can only do better, which is a great thing moving forward.”

Williams ready for next test

Williams will also be keen to avoid falling into an early hole after being dealt a scare when she dropped the first set in her second-round match against American Caty McNally.

The 37-year-old will cap the afternoon session on the main showcourt when she battles Wimbledon quarterfinalist Karolina Muchova for the first time in her career.

“Muchova did well in Wimbledon. Actually got to see some of her matches, but not enough,” Williams said when asked about the test that awaits her in the third round.