NEW YORK – World number six Jessica Pegula reached her first Grand Slam final after staging a thrilling comeback to beat Karolina Muchova 1-6, 6-4, 6-2 in the U.S. Open semifinals on Thursday. The 30-year-old Buffalo native trailed 1-6, 0-2 before coming back to claim her 15th win in her last 16 matches.

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Pegula is the oldest American woman in the Open Era to reach her first Grand Slam final. She is the third American woman aged 30 or older to reach the final of the US Open, joining Serena Williams and Martina Navratilova.

After an injury-plagued start to the season that forced her to miss four WTA 1000 tournaments and the French Open, Pegula started the hard court summer season ranked 20th in the PIF Race to the WTA Finals and can leave New York ranked 3rd. She had a stormy hard court summer, winning her third WTA 1000 title in Toronto, finishing second in Cincinnati and securing a place in the final of the US Open.

Pegula is the fourth player in the Open Era to reach the finals of Canada, Cincinnati and the US Open in one season, joining Rosie Casals (1970), Evonne Goolagong Cawley (1973) and Serena Williams (2013). It is the first time since 2002 that an American man and woman have reached the singles final of a Grand Slam.

Pegula will face world number two Aryna Sabalenka for the US Open title on Saturday. The match is a rematch of last month’s Cincinnati Open final, which Sabalenka won 6-3, 7-5.

History of the volume: Pegula reached her first major semifinal after defeating world number one Iga Swiatek to end her 0-6 drought in Grand Slam quarterfinals. The 30-year-old American was arguably the best player of the summer after winning 14 of her last 15 matches to win the title in Toronto and the final in Cincinnati.

Pegula looked ready to build on that success from the start of the match. She had played Muchova for the first time just three weeks ago in Cincinnati and Pegula won in three sets.

Muchova gets off to a quick start: After an exchange of holds early in the match, Pegula earned three break points when Muchova served at 1-1. Muchova fended off all three chances and from there the Czech turned the tide. After holding at 2-1, Muchova won eight points in a row to extend her lead to 4-1. She unleashed her offensive all-court game to keep Pegula off balance and demoralized the world No. 6 with spectacular shots to win the set after just 28 minutes.

Muchova extended her lead to 2-0 in the second set before Pegula came back. She fended off a break point to keep the score at 2-1 and then earned her first break point against Muchova with a steep return that the attacking Czech could not parry.

As Pegula exerted herself on the baseline to extend the rallies, her luck began to change. She fended off another break point, this time with a well-built nine-shot rally on the baseline, to keep her lead at 3-2. Pegula continued her march, breaking Muchova in a 10-minute match after the latter capitulated with two consecutive backhand errors.

Turning point: Muchova stopped Pegula’s four-game streak with a quick break and then fought back from a 30-0 deficit to level at 4-4. But rather than be discouraged, Pegula held serve quickly and then broke Muchova to force a decider. Muchova made her third double fault of the match on set point, ending the physical 55-minute set and sending the partisan crowd cheering.

Pegula used her momentum to the end. She broke Muchova for 2-0 and fended off a break point with a forehand winner to extend her lead to 3-0. Again, Muchova kept up the pressure and earned a break point from a 40-0 deficit at 3-1. But the tired Czech missed an inside-out forehand and Pegula saved the ball to lead 4-1.

Muchova put up one final resistance. When Pegula served at 4-2, the Czech fought back from a 40-0 deficit to win a break point. She saved five game points before a failed drop shot from the American landed in the net. But Muchova hit a legal backhand and threw her racket in the air in frustration. Pegula held on and made one final break to seal the win after 2 hours and 12 minutes.

Next: Pegula defeated world number one Iga Swiatek in the quarterfinals and will now face number 2 Sabalenka in the second final in a row. Sabalenka leads the head-to-head match 5-2.