French Open champion and former world number one Ashleigh Barty has been knocked out of the US Open thanks to a stunning performance from Wang Qiang. Wang, the 18th seed, triumphed in straight sets, 6-2, 6-4, to secure a place in the quarter-finals. Barty fought hard in the second set, but ultimately hit too many errors to make any inroads on the Wang service game; however, she managed to save three match points before returning a serve long to hand Wang the win. It was the Chinese player's first win over Barty; the Australian had come out on top without dropping a set in their two previous encounters, which both occurred last year – in the quarter-final of Strasbourg, and in the final of the WTA Elite Trophy Zhuhai. Wang will face the winner of the fourth-round match between Serena Williams and Petra Martic.