Jessica Pegula achieved the biggest win of her Grand Slam career by defeating world No. 1 Iga Swiatek 6-2, 6-4 at Arthur Ashe Stadium to advance to her first major semifinal.

Pegula, who had previously reached the quarterfinals in six of her last 14 Grand Slam appearances, had not progressed past the second round in any major this year until now.

This victory marks Pegula’s fourth career win over Swiatek and her first since the 2023 Omnium Banque Nationale. She joins Aryna Sabalenka, Elena Rybakina, and Barbora Krejcikova as one of the only players with four victories over the Polish star, according to WTA statistics.

As the world No. 6, Pegula will face Karolina Muchova, last year’s semifinalist, for a spot in her first major final. Muchova secured her place in the semifinals by defeating Brazil’s Beatriz Haddad Maia 6-1, 6-4 earlier in the day.

Muchova, who was sidelined for nine months due to a wrist injury after her semifinal run last September, made her return with a stint on grass courts in late June. She is the second Czech player in the Open Era to reach consecutive US Open semifinals, following Helena Sukova in 1986 and 1987.

Pegula praised Muchova’s resilience and talent, acknowledging the challenge ahead. “She’s so good, so talented, so athletic. I love how she just comes out and beats everybody despite the injuries,” Pegula said. “I know she has a lot of experience in going deep in Slams, so I’ll need to bring my best game.”

Muchova’s impressive return to form after right wrist surgery in February highlights her strong performance at the elite level.