In her short time at the highest level of her sport, Coco Gauff has built a shining career on grit and resilience, and a rare ability to plot a route to victory even when she cannot find her best level. But deep in the third set against Emma Navarro with her US Open title defence on the line, not even her fighting spirit could paper over the gaping cracks in her game.

A year after becoming a grand slam champion on the same court, Gauff departed Arthur Ashe Stadium following a grim performance in the fourth round of the US Open. The eternally solid Navarro’s resourcefulness and management of nerves helped her move into the quarter-finals on home soil for the first time in her career with a 6-3, 4-6 6-3 win.

With another significant victory, Navarro continues to solidify her status as one of the most improved players on the tour. The 23-year-old American has now defeated Gauff in consecutive grand slam tournaments after also winning their fourth round encounter at Wimbledon to reach her first career grand slam quarter-final.

“I think both of us faced our own struggles at times,” said Navarro. “I think it was a little bit of a battle of will there for a bit. But [I was] proud of my effort today. I was able to stick in there through some tough moments.”

For much of their two hours and 12 minutes on court, Gauff was quite excruciating to watch as she struggled with elementary aspects of her game and her performance underlined the longstanding issues that must be addressed if she wishes to reproduce last year’s results and win another grand slam title.

Gauff’s forehand failed to hold up to sustained pressure from Navarro, then her serve completely malfunctioned, particularly in the final set. She finished with an abysmal 19 double faults, 11 in the final set alone, and her forehand haemorrhaged 29 unforced errors compared to just five winners. The defeat closes out a difficult summer for Gauff that has seen her lose in the round of 16 at Wimbledon, the Olympics and now the US Open.

“Mentally and emotionally I gave it my all,” said Gauff. “Of course, there were things execution-wise, where I wish I could serve better. I think if I would have done that, it would have been a different story for me in the match. But Emma played really well. She did everything well, I thought.”

Navarro, seeded 13th, is a resourceful, efficient player who moves well, has embraced a more offensive mindset in order to compete at the highest level and has few weaknesses in her well-rounded game. She picked things up from where they left off in Wimbledon by being solid off both groundstrokes, maintaining excellent depth and taking her backhand on the rise well.

That depth and consistency produced by Navarro immediately exposed Gauff’s inconsistent forehand and Navarro quickly established a 6-3, 4-3 lead with a second set break. Gauff drew on her mental toughness to reel off three games in a row and force a final set but as Navarro shook off her nerves and remained consistent until the end, Gauff’s serve capitulated throughout the final set. She spent the rest of her night on Arthur Ashe Stadium fighting, and failing, to keep her serve between the lines.

After an extremely successful college career, Navarro, who is the daughter of the billionaire businessman Ben Navarro, only enjoyed her first full year as a professional tennis player last year. She has risen quickly and she could break the top 10 after her results this week. Although she has already exceeded her wildest expectations, her rise is far from over.

“When I first left college, my coach and I kind of made a two-year contract that I would fully commit myself to playing professional tennis for two years and then kind of just reassess after that. I think I hit the two-year mark this June, and we didn’t even acknowledge it or talk about it,” she said. “So, definitely have surpassed my expectations for sure. I hope to just keep getting better.”

In her first US Open quarter-final, Navarro will next face Paula Badosa, the Spanish former No 2, who continued her resurgence from a career-threatening back injury to reach her second grand slam quarter-final with a 6-1, 6-2 win over Wang Yafan of China. Both Navarro and Badosa were born in New York City.

Elsewhere, the ninth seed Grigor Dimitrov held his nerve to defeat Andrey Rublev, the sixth seed, 6-3, 7-6(3), 1-6, 3-6, 6-3 and reach the US Open quarter-finals for the first time in five years. Taylor Fritz, the 12th seed, recovered from a one set deficit to beat the 8th seed Casper Ruud 3-6, 6-4, 6-3, 6-2.

Meanwhile, Jack Draper believes that he is in the process of positioning himself to compete for the biggest titles in the world over the coming years at a time when the next generation of tennis players are beginning to make an impact in the major events.

“I feel a really big opportunity if I stay injury free and if I keep working hard on my body and having the experiences that I’m having playing week in week out, I’m full of confidence that I will be able to get to that top level,” said Draper.

Draper will compete in the fourth round of the US Open for a second consecutive year as he faces Tomas Machac of the Czech Republic on Monday. Both players are seeking their first grand slam quarter-final.