China's Peng Shuai pulled out of the third round of US Open on Saturday for right arm injury.

Peng injured her right arm in women's doubles on Friday, teaming with Su-Wei Hsieh of Chinese Taipei. She lost the doubles 6-3, 3-6, 6-7 (8-6) to Timea Bacsinszky of Switzerland and Tathiana Garbin of Italy.

Peng burst into tears in the news conference after the doubles match for worrying probable withdrawal from the women's singles on Saturday.

Her worry was proved right as she had to make the withdrawal decision on Saturday from the third round.

"Very serious," Peng said of the injury after Friday's doubles match, describing she inflicted the injury when she was trying to smash a high ball at the third set.

After medical check of MRI, Peng was assured to leave the Flushing Meadow without playing, rendering a direct fourth round slot for world 38th ranked German player Andrea Petkovic.

Peng, 61th ranked in WTA, ousted Shelby Rogers in the first round and advanced into the third round by eliminating ninth seed Agnieszka Radwanska of Poland.