WIMBLEDON, England — Unseeded American Alison Riske came from a set down to upset top-ranked Ash Barty 3-6, 6-2, 6-3 at Wimbledon and reach her first Grand Slam quarterfinal.
Riske broke for a 5-3 lead in the deciding set and clinched the win on her first match point when Barty sent a backhand wide.
The loss ends a 15-match winning streak for Barty, who was coming off titles at the French Open and Birmingham and was playing her first tournament as No. 1.
Barty opened the match with four straight aces but landed only 40 percent of her first serves in the second set and was broken four times in total.
Riske is playing in her 30th Grand Slam tournament but her previous best result was reaching the fourth round at the 2013 U.S. Open.
She will next face either Serena Williams or Carla Suarez Navarro.
Also, Zhang Shuai beat Dayana Yastremska 6-4, 1-6, 6-2.
The Associated Press contributed to this report.