Coco Gauff saw the defence of her US Open crown come to an end on Sunday as she suffered a shock defeat to 13th seed Emma Navarro 3-6 6-4 3-6. 

The 2023 champion struggled hugely with her serve and forehand, hitting some 19 double faults, and had to show battling qualities to force a third-set decider before she was eventually beaten anyway by her fellow American in New York.

Navarro, who is through to the quarter-finals of a Grand Slam for the second time in her career and first at the US Open, dominated the first set, and was the player on top in the second too, forcing a break to go 4-3 ahead with a service game to come.

Yet, nerves crept in for Navarro as Gauff rattled off three games in a row to take the contest to a third set.

Into the third, Gauff’s serve let her down badly as Navarro eventually broke twice en route to a stunning victory.

“I lost in the first round the last two years and now to be making the quarter-finals is pretty insane,” Navarro said courtside. “This is the city I was born in and it feels so special to be playing here.

“Coco Gauff is an amazing player, I have a ton of respect for her and I know she’s going to come back here and win this thing again one year.

“It was tough losing the second set, I had chances at 30-0 at 4-3 but had a lull. I was able to re-group and kind of just come into the third set with a fresh mindset.

“I wanted to play aggressive tennis and I think I was able to do that.”

Sky Sports Tennis’ Marion Bartoli said of Gauff’s display: “It’s difficult to win a match with 19 double faults, but also Navarro was causing that by coming forward and really looking to attack.

“She was pushing Coco so far behind the baseline that she could only retreat, that’s not what you want, you want to be in the driving seat.

“Her serve direction she was just constantly targeting Coco’s forehand.”

Navarro will next face Paula Badosa, the 26th seed, who dispatched Yafan Wang of China 6-1 6-2 to advance to her second career Grand Slam quarter-final at the US Open.

The Spain product and former top-five player went 8-for-8 in saving break points and 4-for-5 in converting break points to prevail in one hour, 22 minutes at Louis Armstrong Stadium.

It was a remarkable turn of events for Badosa, who despite being just 26 years old has contemplated retirement due to pain from a stress fracture of her back.

“A few months ago, I was thinking to quit this sport because I stopped believing in myself and my injury wasn’t responding,” said Badosa, who reached the quarterfinals at the 2021 French Open.

“So to be back (at this level) is a dream come true.”

Dimitrov holds off Rublev comeback to make quarters | Fritz beats Ruud from behind

Bulgaria’s Grigor Dimitrov dashed a comeback attempt by sixth seed Andrey Rublev to reach the US Open quarter-finals for the first time since 2019 with a 6-3 7-6(3) 1-6 3-6 6-3 victory on Sunday.

The ninth seed won 80 per cent of his first-serve points and fired 17 aces to frustrate the Russian, who slammed his racket against the Arthur Ashe Stadium court and his own body, which resulted in a cut wrist that required medical attention in the first set.

The evenly-matched clash swung the Bulgarian’s way in the decisive fifth set to the delight of the New York crowd, which included Serena Williams sipping the event’s signature honey deuce cocktail.

Rublev’s frustration spilt over when he started the fourth game of the first set with two double faults, and he blasted a forehand into the net and another wide for Dimitrov’s first break of the match.

Dimitrov looked to be in the driver’s seat after he claimed the final five points of a second-set tiebreak, only to see the Russian battle back to tie the match by seizing the next two sets.

A fourth game break in the final set gave Dimitrov an edge he would not surrender, setting up a quarter-final meeting with either American Frances Tiafoe or Australia’s Alexei Popyrin.

“The steal of the second set really helped me to keep on believing and to keep on trusting in my game and in my body,” Dimitrov told reporters.

“After the first couple of sets, he started playing amazing. I mean, there’s not much else I could have done, so I had to pull the reins back a little bit and wait for an opportunity.

“It happened in the fifth. I think that was the big difference today. After that, I ran with the match, but it was very challenging.”

Earlier, Taylor Fritz overcame a sluggish start to ultimately dominate eighth seed Casper Ruud 3-6 6-4 6-3 6-2 to advance to the US Open quarter-finals for the second straight year.

Ruud was sharp at the outset, breaking for a 5-3 lead before grabbing the first set with a love hold.

But the American began to make inroads against Ruud’s serve in the second and finally converted a break when the Norwegian, who had been using a towel to wipe up his own sweat from the court on a humid day in New York, double-faulted on set point to level the match.

Ruud changed into dry clothes and shoes before the third but never regained his form.

He produced a horrendous service game that ended with him dumping a backhand into the net to fall 2-0 behind in the third and Fritz, seeded 12th, captured the set with an ace.

Fritz kept his foot on the gas in the fourth, hammering his 24th ace on match point to set up a quarter-final meeting with German fourth seed Alexander Zverev after he came from behind to beat American Brandon Nakashima 3-6 6-1 6-2 6-2.

Zverev won 88 percent of his first-serve points and faced just one break point in the match, while he wound up hitting 51 winners to Nakashima’s 18 in a dominant performance.

Zverev, who lost to Daniil Medvedev in the 2020 US Open final, and to Carlos Alcaraz in the final of the French earlier this year, is eyeing a maiden Grand Slam title at Flushing Meadows this week.

“I just need to win one more set than the last two times in the final,” he said. “I am doing everything I can.

“Everything else is out of my power, I am trying my best and hopefully it is going to be enough at some point in my career.”

What’s coming up on Sky Sports Tennis in September?

• Jasmin Open, Tunisia – WTA 250 (9-15 September)
• Guadalajara Open, Mexico – WTA 500 (9-15 September)
• Korea Open – WTA 500 (16 -22 September – with Emma Raducanu in action)
• Thailand Open – WTA 250 (16 -22 September)
• Chengdu Open, China – ATP 250 (18-24 September)
• Hangzhou Open, China – ATP 250 (18-24 September)
• China Open – WTA 1000 (Sept 25 – Oct 6)
• Japan Open – ATP 500 (Sept 25 – Oct 1)
• China Open – ATP 500 (Sept 26 – Oct 2)

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