MONTREAL — Caroline Wozniacki, who retired from a match this week at the Citi Open in Washington, D.C. this week with a left arm injury, has withdrawn from the women's Rogers Cup, organizers announced Friday.

Wozniacki, a former world No. 1 now ranked 58th, has battled injuries this season, including an ankle problem that kept her out of the French Open.

She is the second prominent player to pull out of the Rogers Cup, which begins Monday. Victoria Azarenka announced recently she could not play because she is pregnant.