Updated

Big-hitting Kaia Kanepi has pulled out of the upcoming London Olympic Games due to a heel injury.

The 27-year-old Estonian, who's won a pair of titles on the WTA this year, said she is "very sad" about the withdrawal and is not sure if she'll "ever get another chance to attend the Olympics."

The 16th-ranked Kanepi was also forced to skip the recently-concluded Wimbledon event because of the problematic heel.

She played in the 2008 Games in Beijing and 2004 Olympics in Athens.

The 2012 Olympic tennis event will be held at the All England Club, the venerable site of the Wimbledon Championships.