Thursday's day session of the U.S. Open, dubbed "Doubles on Us" by the USTA, is free.

With the Open returning to a more traditional Grand Slam scheduling format, the only main-draw matches Thursday will be the women's semifinals on Ashe Stadium court at night.

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During the day an array of doubles matches, including the men's and women's semifinals, will be played on the outside courts. Action will also include the junior boys and girls competition, the wheelchair competition and the intercollegiate invitational. Oyster Bay's Julia El Baba will play in the collegiate event. Gates open at 11 a.m. with matches scheduled to start at noon.

"What we are looking to do is promote doubles," tournament director David Brewer said. "And we are promoting it by having people come to the U.S. Open on us . . . We have tons of tennis being played every day, all day on the outside courts. The shift in the schedule gave us the opportunity to promote some things we haven't promoted before."