WASHINGTON (AP) — Vania King and Coco Vandeweghe won Wednesday at the Citi Open to set up an all-American quarterfinal.

The fourth-seeded King beat Irina Falconi 6-2, 7-6 (5), and No. 7 Vandeweghe topped qualifier Aravane Rezai 6-2, 6-2. A third American, third-seeded Sloane Stephens, already advanced to the quarterfinals Tuesday.

King was up 6-5 in the second set and had a chance to win with Falconi serving, but hit a shot wide on match point, then again on the next point and Falconi pulled out the game. On the final match point in the tiebreaker, Falconi hit a shot wide to give King the victory.

Four seeded players have already been knocked out of the women's draw. The latest to go was eighth-seeded Olga Govortsova, who was beaten by 18-year-old Eugenie Bouchard 1-6, 6-0, 6-3. The win put Bouchard in her first career WTA Tour quarterfinal.

Qualifier Jana Cepelova also advanced to her first quarterfinal, beating Edina Gallovits-Hall 6-3, 6-4, and Magdalena Rybarikova topped Eleni Danilidou 6-3, 7-5.

On the men's side, fourth-seeded Tommy Haas beat Leonard Mayer 6-4, 7-5 to set up a quarterfinal with fellow German Tobias Kamke. Kamke beat Marinko Matosevic 6-4, 6-3.