Alison Cornet and Madison Keys out in first round of Citi Open

Alison Cornet and Madison Keys were the high-profile casualties on the opening day of the Citi Open, while veteran Svetlana Kuznetsova breezed through to the second round.

Cornet, who beat Serena Williams en route to the fourth round of Wimbledon, was defeated 7-5, 4-6, 6-4 by American wild card Shelby Rogers.

Rogers will play Marina Erakovic or Kristyna Pliskova in round two.

Kuznetsova comfortably downed Polona Hercog of Slovenia 6-3, 6-2 to progress to a second-round match against either Heather Watson or Kirsten Flipkens.

Seventh-seeded American Keys was beaten 7-5, 6-3 by Japan's Kurumi Nara, who will face Zarina Diyas in the second round.

In the men's draw, qualifier Robby Ginepri of the US beat Alejandro Falla of Colombia 6-4, 6-2 and will take on top-seeded Czech Tomas Berdych in the second round.