Singapore: An all-action Serena Williams eased concerns over her injured knee as she opened the WTA Finals with a 6-4, 6-4 victory over Ana Ivanovic on Monday.
The world number one withdrew from this month's China Open with a left knee problem but she showed no discomfort during an entertaining round robin win in Singapore.
With no strapping on her knee, Williams slid around the court and at one point did the splits. She shouted "Come on!" so many times she made herself hoarse.