Jessica Pegula shrugged off a sluggish start and came back from a set and a break down at the U.S. Open to defeat Karolina Muchova 1-6, 6-4, 6-2 for a berth in her first Grand Slam final.

The No. 6-seeded Pegula, a 30-year-old from New York, has won 15 of her past 16 matches and will meet No. 2 Aryna Sabalenka for the title on Saturday.

Sabalenka, last year’s runner-up to Coco Gauff at Flushing Meadows, returned to the championship match by holding off a late push to beat No. 13 Emma Navarro of the U.S. 6-3, 7-6 (2).

Things did not look promising for Pegula early: Muchova, the 2023 French Open runner-up but unseeded after missing about 10 months because of wrist surgery, employed every ounce of her versatility and creativity, the traits that make her so hard to deal with on any surface.

The slices. The touch at the net. The serve-and-volleying. Ten of the match’s first 12 winners came off her racket. The first set lasted 28 minutes, and Muchova won 30 of its 44 points.

Muchova grabbed eight of the first nine games and was one point from leading 3-0 in the second set. But she couldn’t convert a break chance there, flubbing a forehand volley, and everything changed.

Quickly, the 52nd-ranked Muchova went from not being able to miss a shot to not being able to make one. And Pegula turned it on, demonstrating the confident brand of tennis she used to eliminate No. 1 Iga Swiatek, a five-time major champion, in straight sets on Wednesday. Pegula had been 0-6 in major quarterfinals before that breakthrough.

Took Pegula a while to play that well Thursday, but once she got going, whoa, did she ever. All told, she collected nine of 11 games, a span that allowed her to not merely flip the second set but race to a 3-0 edge in the third.