Serena Williams’s run towards another WTA title has been cut short by a knee injury.
Williams was forced to retire while trailing Wozniak 2-6 1-3 at the Hardcourt event in Stamford on Sunday.
The Canadian qualifier Aleksandra Wozniak will now face French 6th seed Marion Bartoli after Bartoli easily accounted for Japan’s Ai Sugiyama.
Williams got off to a quick start winning the opening game of the first set before Wozniak won the next three and quickly sealed the first set as her opponent started limping.
Williams came out for the second set with her left knee wrapped and after struggling early in the set she was forced to retire just 47 minutes into the match.
"It was hurting in practice, and I didn't really practice for too long because of it," Williams said.
"It didn't bother me until this morning, and during the match, it was getting worse. After I got off the court, it was really swollen.
"I'm not sure how long it'll take to heal. I've been playing a lot of tennis since Miami, especially for me, and these hardcourts can be tough on the body.
"My main goal now is being at the Olympics. I hope to stay healthy. I don't have any plans of not going to Beijing."
