Berrettini has long been blessed with a big forehand, but he and his coach, Vincenzo Santopadre, both spoke afterward about how adding a one-handed backhand slice to his usual two-handed shot on that side helped him against Rublev — and in general.
When Berrettini was 17, he hurt his left wrist and a two-hander just wasn't possible. So Santopadre taught him the single-handed slice and made him use it for a few months. It stuck. Berrettini, who is from Rome, also credited advice he's received from Corrado Barazzutti, whose appearance in the U.S. Open quarterfinals 42 years ago was the only previous time an Italian man made it that far. The country's women have had more success, including in 2015, when it accounted for both final participants: champion Flavia Pennetta and runner-up Roberta Vinci.
Barazzutti is now Italy's Davis Cup captain; Berrettini said they speak to each other every day. He also gets frequent text messages from another past Italian star from decades ago, 1976 French Open champion Adriano Panatta.
"I have to say," recalled Berrettini, who plays No. 13 Gael Monfils of France for a semifinal berth, "he's the first one that told me, 'You're going to serve, like, 220 kph (135 mph). I was 16 when I heard that. I was, like, 'I don't know. (But) if you say that, I'm going to trust you."
TEAM MCOCO IS DONE
The unbeaten streak is over for American teens Coco Gauff and Caty McNally.
Gauff, a 15-year-old from Florida, and McNally, a 17-year-old from Ohio, lost 6-0, 6-1 in the third round of doubles at the U.S. Open to the eighth-seeded team of Victoria Azarenka and Ash Barty 6-0, 6-1.
"We didn't start off good," Gauff said, "and I guess that momentum kind of dragged on the whole match."
It was the first loss for the pairing who nicknamed themselves Team McCoco: They won the junior doubles title at Flushing Meadows together a year ago, then partnered up to win a WTA doubles trophy at the Citi Open in Washington in August, before picking up two victories in New York, drawing big crowds each time.
Both teenagers also drew attention in singles, with Gauff making it to the third round before losing to defending champion Naomi Osaka, while McNally exited in the second round but only after pushing Serena Williams to three sets.
Azarenka and Barty will face No. 1 seeds Timea Babos and Kristina Mladenovic next.
Naomi Osaka thought her emotional interview after her match against Coco Gauff at the U.S. Open would only be seen by those who watched it in-person.
She was surprised to realize it had been seen by many, many more.
"Yeah, definitely didn't expect it to blow up like that," Osaka said.
Following her 6-3, 6-0 victory in the third round, Osaka asked the 15-year-old Gauff to remain on the court with her for an interview in which both players were in tears — as were some folks inside Arthur Ashe Stadium.
"Obviously what Naomi did is what a true champion would do," said No. 13 seed Belinda Bencic, who ended Osaka's title defense by beating her 7-5, 6-4 in the fourth Monday in Ashe.
Osaka thought she noticed some extra support from spectators.
"Definitely felt like people were cheering for me more, which I appreciate," Osaka said. "Yeah, it was kind of unexpected."
Perhaps it wouldn't have been if she had been paying more attention to social media over the weekend.
Osaka said she had her notifications turned off, so she wasn't aware of how many people had been reacting to her gesture.
"But, yeah, I was kind of surprised," she said, "because I just thought it was for the people in there, like, the stands."
AP Sports Writer Brian Mahoney contributed.
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