Women's No. 1 Ash Barty is out of the U.S. Open.
Shelby Rogers took the first set and rallied from three points down in the third to upset Barty 6-2, 1-6, 7-5 (5) at Arthur Ashe Stadium to reach the fourth round.
Rogers had been 0-6 lifetime against top-seeded players.
Rogers, the last American left in the women's draw, was fantastic in the third, hitting backhand winners and using a 103 mph serve to fight her way back against the reigning Wimbledon champion.
Barty had not dropped a set in the tournament but was sloppy from the start. She made 17 unforced errors in the first set and then three more when she held a 5-2 lead in the third that let Rogers back in.