Tough start for Magdalena Rybarikova in Washington

The Slovakian's past two Tour titles have come at the WTA International event, which starts on the hard courts in the United States on Monday.

Unseeded, Rybarikova has drawn Russian second seed Ekaterina Makarova in the first round.

Rybarikova holds a positive 2-0 head-to-head record against the left-hander, but comes into the tournament on the back of a four-match losing run.

For Makarova, the event is her first outing since she reached the quarter-finals at Wimbledon.

Czech Lucie Safarova, who beat Makarova in the last-eight clash at the All England Club on her way to the semi-finals, is the top seed.

Canadian Eugenie Bouchard, runner-up at Wimbledon, withdrew from the tournament due to injury.

American duo Sloane Stephens and Madison Keys are also among the seeds.

Hard-hitting Russian pair Anastasia Pavlyuchenkova and Svetlana Kuznetsova and erratic Romanian Sorana Cirstea should also be among the challengers.

Frenchwoman Alize Cornet is the third seed at the event.

Several of the tour's next generation will be looking to make a run at the title, including Serbian Bojana Jovanovski.

The world number 40 had battled this year before enjoying a good run at the Baku Cup in Azerbaijan.

American Lauren Davis, Kiwi Marina Erakovic and Kazakh Zarina Diyas are among the others competing.