Star flanker Juan Smith has ruled himself out of contention for South Africa's Rugby World Cup squad because of a long-term Achilles tendon injury.

Springbok coach Peter de Villiers announced on Thursday that Smith, a key member of South Africa's 2007 World Cup winning team, had informed him of his decision on Wednesday.

"Juan had been in a race against time to be fit and we were keen to give him every opportunity to prove himself," said De Villiers.

"A fully fit Juan Smith would have been an enormous asset to our campaign and this is a major disappointment. But it was obvious that he was still some way from full fitness and his decision confirms the advice of our medical team."

Smith suffered the injury in a Super 15 match for the Cheetahs in February.

He said: "I've worked very hard to get back on the training field but I'm still some way from full fitness and have been training with quite a lot of pain."

The Springbok World Cup squad will be announced on Tuesday.

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