WASHINGTON — Top-seeded Sloane Stephens has been upset in straight sets in the first round of the Citi Open.
Rebecca Peterson beat Stephens 6-2, 7-5 on Tuesday at the hard-court tournament that serves as a tune-up for the US Open. Stephens was coming off a third-round loss at Wimbledon.
Stephens is ranked eighth, and Peterson is 70th. Stephens won the Citi Open in 2015 and reached the 2017 doubles final. Peterson, from Sweden, will face American Sachia Vickery or Italian Camila Giorgi in the second round.
In other action in Washington, eighth-seeded Monica Puig of Puerto Rico defeated American Allie Kiick 6-4, 6-2. Coco Gauff, the 15-year-old who reached the fourth round at Wimbledon and got into the Citi Open as a qualifier, faces Zarina Diyas later Tuesday.
In the men’s draw, Jo-Wilfried Tsonga faces second-seeded Karen Khachanov.