Quote of the Day: Coco Gauff's comeback inspiration? "I can't lose in front of Justin Bieber!"

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Deep in the second set of her tough third-round battle against Elise Mertens, Coco Gauff looked up to the Jumbotron inside Arthur Ashe Stadium. The American was down a set and had just traded breaks of serve with her opponent, locked in battle with her US Open second week hopes teetering.

That’s when the screens showed pop megastar Justin Bieber and wife Hailey Bieber taking in the action from the Emirates suite, and NBA star and avid tennis fan Jimmy Butler watching on in the background.

The 19-year-old says she was ‘starstruck’ at the sight—and suddenly she was even more highly motivated to bring out her best tennis against Mertens.

“I was like, ‘I can’t lose in front of Justin Bieber!’” Gauff told ESPN afterward. “I didn’t lose a game after I saw him.” The world No. 6 indeed completed a 3-6, 6-3, 6-0 comeback without dropping a game—or even facing a break point—in the third set.

Afterward, she told press she felt ‘honored’ at the growing constellation of celebrities who have been supporting throughout the fortnight—from Bieber and Butler to former U.S. President and First Lady Barack Obama and Michelle Obama.

Q. What does it feel like to have these big names coming to watch you play? Is there any celebrity you'd feel starstruck seeing in the crowd?

It's crazy. I've come to the Open for years. Being a fan, just looking in the crowd to see who's coming, looking in the president box, the suites, to see who's there... Now being a player, it's really crazy.

I was definitely starstruck with Justin Bieber. ‘Never Say Never' was one of my favorite songs when I was a kid. Then 'Baby, Oh, Baby'. I could go through all his songs. Then Hailey, too, coming—I guess it was a little date night for them, which was really cool.”

Obviously Jimmy Butler, he's came to a couple of my matches. I wasn't as surprised he was there. I still am like, Man, this guy is busy, why is he coming to watch me play?

It's a really cool experience. Yeah, I'm just happy I guess and really honored.

I guess which celebrity I would be starstruck, definitely Beyonce. If she ever came, oh, my goodness, I hope they would not show her on the screen. Maybe at the end (smiling).

A quarterfinalist in Queens last year, Gauff quickly became a US Open favorite after clinching her second title of the year in Washington D.C. and then lifting the biggest trophy of her career at the WTA 1000 in Cincinnati. Behind the scenes, the American has put together a new coaching team led by Pere Riba and co-helmed by Brad Gilbert.

The result has been a big-hitting Gauff that’s high on confidence, and enjoying every minute of her time at the US Open.

“Today was just a fun night,” she grinned. “Playing on Ashe, I don't think there's anything like it, especially when you win like a long rally. I was saying that with my team today, there's nothing like that. No tennis atmosphere matches to nighttime an Ashe, honestly.

“I've played in pretty much all of them at this point, and there's nothing that compares to Arthur Ashe at night.”

No. 6 seed Gauff will face the resurgent Caroline Wozniacki in the fourth round on Sunday.