(AP)–Serena Williams tied Martina Navratilova’s professional-era women’s record with her 306th career victory in a Grand Slam match, beating Vania King 6-3, 6-3 to reach the U.SOpen’s third round.

Serena Williams, of the United States, prepares to return a shot from Ekaterina Makarova, of Russia, during the first round of the U.S. Open tennis tournament, Tuesday, Aug. 30, 2016, in New York. (AP Photo/Darron Cummings)

Serena Williams, of the United States, prepares to return a shot from Ekaterina Makarova, of Russia, during the first round of the U.S. Open tennis tournament, Tuesday, Aug. 30, 2016, in New York. (AP Photo/Darron Cummings)

Hitting 13 aces Thursday night with the roof closed at Arthur Ashe Stadium, Williams improved to 306-42 in matches at major tournaments, a winning percentage of .879.

Music power couple Beyonce and Jay Z sat behind Williams’ coach Patrick Mouratoglou in the player’s guest box.

Music artists Jay Z, left, and Beyonce, talk while watching play between Serena Williams and Vania King, of the United States, during the second round of the U.S. Open tennis tournament, Thursday, Sept. 1, 2016, in New York. (AP Photo/Julio Cortez)

Music artists Jay Z, left, and Beyonce, talk while watching play between Serena Williams and Vania King, of the United States, during the second round of the U.S. Open tennis tournament, Thursday, Sept. 1, 2016, in New York. (AP Photo/Julio Cortez)

Only Roger Federer, with 307, has won more Grand Slam matches than Williams in the Open era, which dates to 1968.

Williams can match Federer’s total by beating 47th-ranked Johanna Larsson of Sweden on Saturday.