Pegula rose two places to a career-best No. 3 on Monday, a day after winning the biggest title of her career at the Guadalajara Open in Mexico.
Pegula is a 28-year-old from New York, and her parents own the NFL’s Buffalo Bills and NHL’s Buffalo Sabres. She reached the quarterfinals at three of this year’s four Grand Slam tournaments before losing to the eventual champion and No. 1 seed each time: Ash Barty at the Australian Open, and Iga Swiatek at the French Open and U.S. Open.
Gauff, who lost in the quarterfinals at that tournament, moved up from No. 7 to No. 4.
The last time two Americans were that high in the women’s tennis rankings was the week of Oct. 18, 2010, when Serena Williams was No. 2 and Venus Williams was No. 4. Both of the siblings already had been No. 1 prior to that.
Gauff is an 18-year-old from Florida who was the runner-up to Swiatek at Roland Garros and made it to the quarterfinals at the U.S. Open.
The two of them are doubles partners and in the top four in that discipline, too: Gauff is ranked No. 2, Pegula No. 3.
Swiatek maintained her hold on No. 1 in the singles rankings Monday, followed by No. 2 Ons Jabeur, who was the runner-up at Wimbledon and the U.S. Open.
In addition to that quartet atop the rankings, the other four women who qualified in singles for the WTA Finals, which are in Fort Worth, Texas, from Oct. 31 to Nov. 7 are Caroline Garcia, Aryna Sabalenka, Daria Kasatkina and Maria Sakkari.
There were no changes in the top eight places in the ATP men’s rankings, with Carlos Alcaraz retaining the No. 1 spot he earned by winning his first Grand Slam title at the U.S. Open last month.
He’s followed by 23-time major champion Rafael Nadal at No. 2, with Nos. 3-8 still Casper Ruud, Daniil Medvedev, Stefanos Tsitsipas, Alexander Zverev, Novak Djokovic and Andrey Rublev.
Felix Auger-Aliassime’s title at Antwerp, Belgium, on Sunday — his second trophy in a row — allowed him to move up from No. 10 to No. 9, swapping places with Taylor Fritz.