In a mutinous fourth round at Roland Garros that featured two teenagers, two 20-year-olds and a whopping seven players competing in their first French Open, a few of that young and inexperienced lot climbed out of the rubble Sunday to prove themselves the real deal.

Start with the teenagers because they deserve it.

Polish 19-year-old Iga Swiatek kicked off a day of upsets with a resounding, 6-1, 6-2 win over top-seeded Simona Halep, the two-time Grand Slam champion who had been practicing exclusively on clay for months and was the heavy favorite to win a second French Open title next weekend.

She was joined hours later by 19-year-old Italian Jannik Sinner, whose bullwhip of a forehand helped him upset recent U.S. Open finalist Alexander Zverev, 6-3, 6-3, 4-6, 6-3, to become the first man to reach the quarterfinals in his debut at Roland Garros since some guy named Rafael Nadal did so 15 years ago (and then went on to win the whole thing).

Sinner will face Nadal, who enforced some sense of order Sunday and dispatched 20-year-old Floridian Sebastian Korda, 6-1, 6-1, 6-2, in the quarterfinals. Korda was another French Open first-timer.

“I just think it's really nice that we have many young players that are coming up and that are not scared,” Swiatek said. “I'm really happy I'm one of them."

Theories about why so many upstart young players have flourished at this year’s French Open, with everything from the unusual timing of the event to the cold weather to the chopped-up tennis season staking a claim.

But Swiatek and Sinner played matches that would impress under any conditions.

Sinner’s cracking groundstrokes rarely missed. The Italian dominated the match against the occasionally uneven Zverev, who said in a news conference after that he has been feeling sick and had a fever of 38 degrees Celsius (100.4 Fahrenheit).

“What can I say? I’m completely sick,” said Zverev, who declined to say when he was last tested for the novel coronavirus. “I can’t really breathe, as you can hear by my voice."

Players in the controlled environment at the French Open are tested every fifth day.

Swiatek’s upset of Halep was perhaps the most unexpected result even in a women’s event rife with surprise — only six seeded women made the round of 16.

Halep, ranked second in the world, had won a career-best 17 straight matches in 2020 and collected two clay-court titles in the lead-up to the French Open.

Swiatek, ranked 54th, played nearly without flaw. She showed off an all-court game and crushed Halep’s many short groundstrokes with precision and pace in her second appearance in the fourth round at Roland Garros. Halep beat her at the same stage in Paris last year, swatting her aside in a 45-minute match in which Swiatek won just one game.

This year, Swiatek arrived with a renewed focus having completed her high school degree during tennis’s coronavirus hiatus but, critically, feeling less pressure.

She has faced big stages before, not just at Roland Garros last year but in the fourth round of the Australian Open this year as well. With powerful groundstrokes and a deft touch at the net, Swiatek hasn’t dropped a set in Paris.

She quickly became the new favorite to win a tournament in which only four of 32 seeded women remain.

“Basically, everything was different [compared with last year’s match],” Swiatek said. “… I’m glad that I wasn’t in a final of the French Open last year because I think the pressure would be too big. I like that I have time to grow up. I think it’s perfect for me doing it one step after another.”

Said Halep: “I’m not going to ruin the whole year just for a match. Of course it’s not easy to take it, but I’m used to some tough moments in this career. So I will have a chocolate, and I will be better tomorrow."

Swiatek moves on to face Italian Martina Trevisan, one of two women in the fourth round who came through qualifiers to reach the main draw. In just the second Grand Slam of her career, the 159th-ranked Trevisan upset fifth-seeded Kiki Bertens, 6-4, 6-4, on Sunday.

Trevisan beat American phenom Coco Gauff and No. 20 seed Maria Sakkari en route to the fourth round and sealed her match Sunday with an expert backhand lob.

“I didn’t see exactly the mark where it hit, but I saw the face of Bertens, and I say: ‘Okay, it was good. It’s good,’ ” Trevisan said.

The other qualifier also advanced Sunday: World No. 131 Nadia Podoroska beat Barbora Krejcikova, 2-6, 6-2, 6-3, to become the first Argentine woman to reach the French Open quarterfinals since Paola Suarez in 2004.

“It’s not a surprise, these results,” Halep said. “Everyone at this level is playing really well, and in the fourth round of a Grand Slam it’s not a surprise anymore because if you are there it means that you have a great game.”

The results may not be a surprise to Halep, but they will force tennis fans to learn a few new names.

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