Venus Williams of the US. plays against China's Peng Shuai. [Photo/Agencies]

After Peng began to find her footing and took the first set, she found the motivation to power through her opponent's serves.

Peng was also circumspect after the surprise win. She said there were still places where she thought her game was not where it needed to be.

Peng said she is not thinking about recent setbacks and declines in her performance and ranking. She said she is motivated simply by the chance to play more tennis.