While Serena Williams, the most dominant player in tennis history with 23 Grand Slam singles titles, is home with her newborn baby, her countrywomen are dominating at the U.S. Open: all four semifinalists are American.

“We’re gonna have four American women playing tomorrow, and that’s pretty awesome,” No. 15 seed Madison Keys said after winning her quarterfinal match. “We all were rooting for each other today.”