The Williams sisters play only the occasional doubles tournament, at the Grand Slams, so they came in unseeded. But they own three Olympic doubles gold medals and 13 major titles.
Wednesday they were at Louis Armstrong Stadium, and after eighth-seeded Richard Gasquet had finished beating fourth-seeded David Ferrer in an entertaining five-setter, 6-3, 6-1, 4-6, 2-6, 6-3, at Arthur Ashe Stadium, there was almost a stampede of fans rushing over to watch the Williams sisters.
This is only the second tournament of the year in doubles for the Williams sisters.
"We love playing on this court," Venus said. "It's awesome."
Serena, who will play China's Li Na in the singles semifinals Friday, said playing doubles Wednesday and again Thursday will help her. "Having two days off, it feels good to keep having matches. Today and tomorrow will definitely help me for my singles match."
She won her quarterfinal 6-0, 6-0 Tuesday, and Serena said being tired wasn't a problem.
Venus said she and her sister learned from their loss at the Australian Open to the Italians. "They played well and they play often. But we learned."