American Pegula into 4th Rd for 1st time | US Open updates

Petra Kvitova, of the Czech Republic, reacts after defeating Garbine Muguruza, of Spain, during the third round of the U.S. Open tennis championships, Saturday, Sept. 3, 2022, in New York. (AP Photo/Eduardo Munoz Alvarez)

Jessica Pegula, of the United States, reacts after defeating Yuan Yue, of China, during the third round of the U.S. Open tennis championships, Saturday, Sept. 3, 2022, in New York. (AP Photo/Eduardo Munoz Alvarez)

Garbine Muguruza, of Spain, reacts after scoring a point against Petra Kvitova, of the Czech Republic, during the third round of the U.S. Open tennis championships, Saturday, Sept. 3, 2022, in New York. (AP Photo/Eduardo Munoz Alvarez)

Serena Williams, of the United States, waves to fans after losing to Ajla Tomljanovic, of Austrailia, in the third round of the U.S. Open tennis championships, Friday, Sept. 2, 2022, in New York. (AP Photo/John Minchillo)

Rafael Nadal, of Spain, celebrates after defeating Fabio Fognini, of Italy, during the second round of the U.S. Open tennis championships, Friday, Sept. 2, 2022, in New York. (AP Photo/Frank Franklin II)

Iga Swiatek, of Poland, returns a shot to Sloane Stephens, of the United States, during the second round of the U.S. Open tennis championships, Thursday, Sept. 1, 2022, in New York. (AP Photo/Mary Altaffer)