When she was struggling earlier this year, Jessica Pegula wasn’t sure if some of the dramatic changes she made in pursuit of better results were going to ultimately pay off. 

But at this year’s U.S. Open, those doubts have been answered. Pegula isn’t just playing the best tennis of her life, she’s now gone further at a Grand Slam than ever before — with a real chance to take home the trophy. 

Pegula, the 30-year-old daughter of Buffalo Bills owners Terry and Kim Pegula, reached the U.S. Open semifinals with a dominant 6-2, 6-4 victory Wednesday over world No. 1 Iga Swiatek. It’s the first time Pegula has broken through the Grand Slam quarterfinal barrier after six attempts, including a 6-3, 7-6 loss to Swiatek at the U.S. Open two years ago. 

But this is a different Pegula, who split with longtime coach David Witt in February after a disappointing second-round exit at the Australian Open. Pegula missed the clay court season this year with a rib injury, returned at Wimbledon where she also lost in the second round and didn’t seem likely to be a factor for the rest of 2024. 

But Pegula found her form after the Olympics, defending her title at the Canadian Open and reaching the final the following week in Cincinnati. All told, she has won 14 of her last 15 matches heading into Thursday’s semifinal matchup against Karolina Muchova. 

Still, Pegula was considered an underdog to Swiatek, the 2022 U.S. Open champion. Swiatek led their head-to-head rivalry 6-3 coming into the match.

But from the very beginning Wednesday, Pegula was dialed in tactically and playing confident tennis both on her forehand and backhand. Pegula’s hard, flat ball strike appeared to rush Swiatek, who never got into a good rhythm and made uncharacteristic mistakes off standard groundstrokes. She finished with 41 unforced errors to just 12 winners. Pegula played a much cleaner match, making 65 percent of her first serves and just 22 errors. 

Only one Grand Slam champion remains among the final four in the women’s draw. No. 2 seed Aryna Sabalenka is a two-time Australian Open champion and lost last year’s U.S. Open final to Coco Gauff. She will face American Emma Navarro on Thursday. 

Regardless of what happens from here, Pegula, the No. 6 seed, will leave the U.S. Open as the top-ranked American woman. 

“I just kept losing but to great players,” Pegula said on ESPN about her previous quarterfinal struggles. “I know everyone keeps asking me about it, I just didn’t know what else to do. I just needed to get there again and win the match. Finally I’m able to say I’m a semifinalist.”

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