NEW YORK, NY, USA - Coco Gauff had no tears left to cry by the time she had arrived for her post-match press conference after a straight-sets defeat to defending champion Naomi Osaka, saluting the top seed and World No.1 for her kind words after the match.

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"I think she just proved that she's a true athlete," she said Saturday night. "For me the definition of an athlete is someone who on the court treats you like your worst enemy but off the court can be your best friend. I think that's what she did tonight."

Gauff was in the midst of her US Open main draw debut and has been on a meteoric rise that began when she reached the final of the junior singles tournament as a 13-year-old in 2017. Less than two years later, she stunned Venus Williams en route to the second week of this year's Wimbledon Championships and the 15-year-old enjoyed another fairytale after thrilling wins over Anastasia Potapova and Timea Babos.

"A lot can happen in a year. Last year, I was preparing for juniors. I lost in the quarterfinals last year. Now I almost got to the second week. I got to the third round in my first main draw US Open. I'm super proud of myself.

For me, I'm just going to continue to learn. My dad told me I'm 15, I still have a lot to work on, a lot to improve."

Playing on Arthur Ashe Stadium for the first time in her young career, Gauff found herself outmatched against the top seed - with whom she has sometimes practiced at home in Florida - but was reinvigorated after Osaka invited the American to share the stage for a joint on-court interview.

"She really showed sportsmanship tonight. I wasn't expecting it. I'm glad that I was able to experience that moment. I'm glad the crowd was kind of helping me and her."

In an emotional moment for all involved, Gauff laughed at the scene that saw both young women in tears.

"She was crying, she won. I was crying. Everybody was crying. I was like, 'I don't know why she was crying. You won the match!'"

Resolved to earn another shot on the Grand Slam stage, the youngster appeared undaunted by her ostensibly overnight turn from Wimbledon qualifier to 'the future of American tennis,' eager to do all she can to compete with the best in the world.

"I think I'm just moving the pace that Coco can go. Everyone is different. I feel like everyone peaks at different points in their life.

"I wouldn't consider right now a peak because I do feel like I can improve a lot. I think for me, I'm just moving the right pace for Coco. Maybe this pace might not be the right pace for someone else. I think just everyone is different.

"I think everything happens for a reason. So I just think regardless of age or stage, I think that pace in general is different for everybody. Some people peak late in their careers, some people peak early.

"Right now I'm doing well, but I wouldn't consider this a peak for me because I still think I can improve a lot."

Looking back on her whirlwind week at the US Open, Gauff takes only positives both from the last three months and the tournament itself, which still continues in doubles alongside countrywoman and fellow Citi Open champion Caty McNally.

"I guess coming into this, I knew that a lot more people were watching me at Wimbledon, expecting things from me. I think I try my best to zone out everyone, and just focus on me.

"I think a lot of people just forget that I'm new to this, I'm still learning, and I'm still improving. I think a lot of people came in here with a lot of expectation, just not even this tournament, but after Wimbledon in general.

"Between Washington and then maybe a week before US Open, I felt pressure to kind of just prove myself. I think maybe like three or four days before my first match, I think I kind of realized I just need to have fun out there. Whatever happens happens. But as long as I have fun, that's important for me."