Coc0 Gauff completed the first week of the U.S. Open in successful fashion as she defeated Caroline Wozniacki in a grueling three-set match Sunday. Gauff became the first American teenager since Serena Williams to reach the quarterfinals.

Gauff pulled off a 6-3, 3-6, 6-1 triumph, taking charge in the final set with her raz0r-sharp ground strokes and accurate serve. Wozniacki won the second set to tie the match and took a 1-0 lead in the third set, but Gauff turned it up a notch after that and won the final six games.

She let looser with an emotional roar after the final point. She quickly regained her cool and praised Wozniacki in the post-match interview, and thanked the fans for supporting her. “I know how popular Caroline is, but you gave me so much support and I appreciate that,” Gauff said.

Gauff seemed to lose much of her concentration during the second set as she made 22 unforced errors that allowed Wozniacki to get back in the match. Coach Brad Gilbert seemed to be giving her advice after nearly every point, and she asked him to stop as the set slipped away.

Wozniacki was making her return to tournament tennis after a 2-year retirement. She has played in 3 tournaments since coming back, and the 33-year-old mother of two was able to push the young American star quite a bit before hitting a wall in the final set.

Coco Gauff is hoping to continue her run towards a Grand Slam title in the second week of the tournament. She will face either No. 1-ranked Iga Swiatek or No. 20 Jelena Ostapenko in the quarterfinal round.