Sharapova withdraws from Stanford Classic with injured arm

Five-time Grand Slam champion Maria Sharapova has withdrawn from the Stanford Classic ahead of her second round match due to soreness in her left arm.

"Unfortunately, I have to withdraw from today's match," Sharapova said in a statement.

"Toward the end of Monday night's match, I felt pain in my left forearm. After yesterday's scan, the doctor has recommended I don't risk further injury. Monday night's crowd was so special and I wish I could continue playing, but I have to make a preventative decision," she added.

She was competing as a wildcard in her fourth tournament after a 15-month doping ban.

The Russian player was scheduled to lock horns with Ukraine's seventh seed Lesia Tsurenko for a place in the semi-finals.

Her early exit means Tsurenko advances to the third round by walkover.

Sharapova made her return to the WTA after eight weeks away with a leg injury on Monday in Stanford, where she defeated Jennifer Brady, 6-1, 4-6, 6-0.

"This is definitely tough for Maria," said Bank of the West Classic tournament director Vickie Gunnarsson.

"She has so many fans which was evident by the support she received here on Monday night. We wish her a speedy recovery and hope to see her back on the court soon."

The 30-year-old Russian, banned after testing positive for heart drug meldonium at the 2016 Australian Open, has had mixed results since re-joining the WTA Tour.