Flavia Pennetta
Flavia Pennetta reacts after upsetting Simona Halep in the U.S. Open semifinals. Getty Images

While Serena Williams won’t be playing to put her name in the record books, a different kind of history will still be made in Saturday’s U.S. Open final. At the age of 33 and 32, respectively, either Flavia Pennetta or Roberta Vinci will become the oldest female winner of the U.S. Open in the Open era, as well as the oldest first-time Grand Slam winner.

Surely neither could have envisaged being just one match away from such an achievement two weeks ago, let alone the identity of the last woman standing in their way of the trophy.

“It’s amazing because also 20 days ago my physio asked me if I ever thought I could win a Grand Slam or be in the final of a Grand Slam,” Pennetta said after upsetting second seed Simona Halep in the semifinals. “I said no. For a lot of reasons my answer was no, but like always you never know. You just have to play and try your best and good things come when you never expect them most of the time. When you want something too much and you’re really saying ‘this is the moment I have to do this and that,’ always it’s going to be a big mess.”

And it certainly appeared that the weight of expectation was what derailed Williams in Friday’s dramatic second semifinal. Closing in on a first calendar-year Grand Slam since 1988 as well as equaling Steffi Graf’s Open-era record of 22 Grand Slam titles, Williams was beaten by Vinci in three sets in what was one of the most stunning upsets in tennis history.

Like Pennetta, Vinci’s greatest success in her career has come in doubles, where she has completed a career Grand Slam. Unseeded and playing in her first ever Grand Slam final, few gave her a chance against the dominant world No. 1. But her near-faultless composure and all-court game held firm as the pressure overwhelmed he opponent. Prior to that contest, Vinci had not played a single seed in this year’s U.S. Open, having benefited from Maria Sharapova’s withdrawal, first-round exits for Ana Ivanovic and Carla Suárez Navarro and a freak locker-room fall that led Eugenie Bouchard to pull out ahead of their fourth-round match. Yet she has now conquered the greatest challenge in all of women’s tennis.

While 26th seed Pennetta didn’t quite have to do that, she has not had things easy en route through to Saturday’s all-Italian affair. As well as former champion Sam Stosur, Pennetta ousted two-time Wimbledon champion Petra Kvitova before breezing past Halep. The way both she and Vinci dealt with closing out the biggest wins of their respective careers bodes well for a high-quality final. Yet, both will now have to deal with the pressure of an occasion neither could have foreseen.

Scheduled start time: The match won't take place before 3 p.m. EDT

TV channel: ESPN

Live stream: ESPN3, Watch ESPN