This year, Jessica Pegula found herself in a tough spot; she had made significant adjustments to her game but was uncertain if they would lead to success.

However, during this year’s U.S. Open, Pegula’s hard work has clearly paid off. She’s not only showcasing some of the best tennis of her career but has also advanced further in a Grand Slam tournament than ever before, giving her a solid chance at winning.

Pegula, 30, the daughter of Buffalo Bills owners Terry and Kim Pegula, achieved a remarkable 6-2, 6-4 win on Wednesday against world No. 1 Iga Swiatek, reaching the U.S. Open semifinals. This is Pegula’s first time breaking through the quarterfinal stage at a Grand Slam after six previous attempts, which included a loss to Swiatek in the same round at the U.S. Open two years ago.

Quite different from before, this Pegula made a significant change by parting ways with her coach David Witt in February following a disappointing exit in the second round of the Australian Open. She also missed the clay court season due to a rib injury, and her return at Wimbledon ended with another second-round defeat, making her potential success in 2024 seem unlikely.

After the Olympics, Pegula regained her form, successfully defending her title at the Canadian Open and finishing as a finalist the next week at Cincinnati. In total, she has won 14 of her last 15 matches leading up to the semifinal against Karolina Muchova on Thursday.

Despite her achievements, many viewed Pegula as the underdog facing Swiatek, the reigning U.S. Open champion. Before their match, Swiatek led their head-to-head record 6-3.

From the start of Wednesday’s match, Pegula displayed impressive tactical awareness and played with confidence, effectively controlling her forehand and backhand. Her strong, flat strokes seemed to throw Swiatek off balance, preventing her from settling into her rhythm, resulting in Swiatek accumulating 41 unforced errors compared to just 12 winners. Pegula maintained a clean match with 65 percent of her first serves landing in and only committing 22 errors.

Among the final four in the women’s draw, only one has previously won a Grand Slam: No. 2 seed Aryna Sabalenka, a two-time Australian Open champion who lost to Coco Gauff in last year’s U.S. Open final. She is set to play American Emma Navarro on Thursday.

No matter the outcome of the remaining matches, Pegula, the No. 6 seed, will finish the U.S. Open as the highest-ranked American woman.

“I just kept on losing, but to outstanding players,” Pegula reflected on her prior quarterfinal challenges in an interview with ESPN. “Everyone keeps asking, and I just didn’t know how to respond. I needed to get to this point and finally win a match. Now, I am thrilled to call myself a semifinalist.”

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