Estonia's Kaia Kanepi has withdrawn from the Olympic Games with a heel injury.

The 27-year-old had expected to recover in time to represent her country at the Games, with the tennis taking place at Wimbledon.

However, following an ultrasound examination, it has been decided that the problem has not subsided enough for the former Wimbledon quarter-finalist to take her place in the draw.

"It's very sad that I cannot participate in the Olympics," she told her official website. "I do not know if I will ever get another chance to participate in the Olympic Games.

"At the moment all I want is my legs to be ok and that I could play tennis without feeling any pain."

Kanepi had been considered one of Estonia's best hopes for a medal in London.