Maria Sharapova and her run with injuries continued after she withdrew from the Western and Southern Open on Tuesday.

Sharapova was set to play Varvara Lepchenko in the second round in Cincinnati, but the world number two succumbed to an ongoing right leg injury, tournament officials confirmed.

The 28-year-old, who is hopeful of being fit for the US Open which gets underway in New York on August 31, has been replaced in the draw by lucky loser Mirjana Lucic-Baroni.

Sharapova - 34-7 on tour this season - missed the Rogers Cup in Toronto due to the same injury, meaning she has not played since losing to world number one Serena Williams in the Wimbledon semi-finals last month.

American veteran Venus Williams withdrew from the Western and Southern Open because of a viral illness as Ana Ivanovic moved into the round of 16.