Gauff has won three WTA Tour titles this seasonVenue: Flushing Meadows, New York Dates: 28 August-10 SeptemberCoverage: Daily live text and radio commentaries across the BBC Sport website, app, BBC Radio 5 Live and 5 Sports ExtraCoco Gauff underlined her credentials as one of the US Open title favourites with a gutsy victory over Caroline Wozniacki to reach the quarter-finals.
The 19-year-old American had to come back from a break down in the third set to win 6-3 3-6 6-1.
Sixth seed Gauff is bidding for a first Grand Slam title.
The victory also ended Wozniacki's extraordinary comeback run after a three-and-a-half-year absence from the sport.
Gauff arrived at her home Grand Slam full of confidence after title wins in Washington and Cincinnati.
Her fine form looks set to continue as she showed great resilience to fight back in the third set and register an impressive win against a resilient Wozniacki.
Gauff joked afterwards that her father can no longer sit in her support box because he gets too nervous during matches.
"He's been doing laps around the stadium," she said.
"I don't know if he can hear me but I felt his good energy even if I couldn't see him."
Gauff will face either defending champion Iga Swiatek or former French Open winner Jelena Ostapenko next.
Broken in her opening service game, Gauff was able to overcome a nervy start to level the scores at 2-2 before getting the decisive break to lead 5-3 and serve out the opener on the third set point.
Despite saving five break points in the second set, a frustrated Gauff eventually conceded serve to trail 5-3 and allow Wozniacki to take the fourth-round tie to a decider.
The teenager found herself a break down once again at the start of third and directed her frustration towards her coaching team, shouting at them to stop talking to her.
The home favourite channelled her energy well, overturning the deficit and breaking Wozniacki to take control of the set, all the time roared on by the crowd inside Arthur Ashe Stadium.
There was little Wozniacki could do as her spirited opponent, serving for the match, raced out to a 40-0 lead before wrapping up victory at the second opportunity.
Asked about her relationship with her coach afterwards, Gauff said shouting at the player's box was a "stress reaction".
"My whole box were cheering for me. They're the ones that are giving me the game plan," she said.
"Sometimes I do tell them to chill a little bit."
'Gauff in best possible position'
Since her disappointing first-round exit at Wimbledon in July, Gauff has only lost one of her last 16 matches and is currently on a nine-match winning streak.
The world number six has only got to one Grand Slam singles final before - the 2022 French Open, where she lost 6-1 6-3 to Swiatek.
The top seed could be Gauff's quarter-final opponent if the Pole beats Ostapenko later on Sunday, but former British number one Annabel Croft says the American has "put herself in the best possible position" to beat Swiatek.
"I think this was a great test for her. She had to really fight and be physical," Croft added.
"She had to go toe-to-toe and I think the quality of the tennis and the ball striking was phenomenal."
Guaff beat Swiatek on her way to claiming the biggest title of her career at the Cincinnati Open last month.
"I don't think about the two titles. They're in the past and I'm really focused on this tournament," said Gauff, who went out at the quarter-final stage at last year's Flushing Meadows.
"I have confidence in myself that I can go even further."
