This will be the first Grand Slam final between two Italians Flavia Pennetta and Roberta Vinci as well as 2 women over thirty in the open era

Twenty-six times, Serena Williams had played a grand slam match in 2015. And all 26 times she emerged triumphant.

But in her 27th encounter, the world No. 1 came unstuck against a stubborn Italian, Roberta Vinci, who wasn’t even seeded at the U.S. Open.

Vinci, best known for formerly being the world’s top-ranked doubles player, stunned Williams 2-6 6-4 6-4 in one of the greatest shocks in tennis history to end the American’s chances of completing the calendar-year grand slam.

Williams had toiled in quite a few of her past grand slam tussles this year but always found a way to win. Not against the 43rd-ranked Vinci, though, who not only overturned a set deficit but came back from 2-0 down in the third against the three-time defending champion.

“I don’t want to talk about how disappointing it is for me,” Williams began in her press conference, which was brief. “If you have any other questions, I’m open for that.”

Prior to Friday, Vinci lost all four of their head-to-heads without claiming a set.

So, instead of Williams trying to emulate Steffi Graf’s achievement of 1988, it will be an all-Italian U.S. Open final Saturday after Flavia Pennetta upset second-ranked Simona Halep 6-3 6-1 in Friday’s first women’s semifinal. That was a minor upset in comparison to Vinci’s scalp.

They’re probably saying “Forza Italia” back in Italy.

The fans who’ll show up in New York will thus be watching history, just not the type they were expecting.

“I don’t think I played that bad,” said Williams. “I made more unforced errors than I normally would make, but I think she just played really well. She did not want to lose today. Neither did I, incidentally. But she really didn’t, either.”

Williams discounted pressure being a factor in the defeat.

“I told you guys I don’t feel pressure,” she said. “I never felt pressure. I never felt that pressure to win here. I said that from the beginning.

“I made a couple of tight shots, to be honest, but maybe just about two.

“But that, I think … in any normal match you make two tight shots. Other than that, I don’t think I was that tight.”

Vinci disagreed.