South African flanker Juan Smith has been ruled out of next month's World Cup in New Zealand by an Achilles tendon injury.
The 30-year-old suffered the injury during the South African Super Rugby season and had undergone surgery to try to rectify the problem.
Smith was expected to miss the Springboks' Tri-Nations match with New Zealand on Saturday but he has failed to recover sufficiently and will now miss the World Cup.
"I won't be able to give everything and realise I should put my team, teammates and the Bok fans first," Smith told the Volksblad newspaper.
"I must stop lying to myself - what I've been doing these last three weeks - and realise that I'm not ready."
Smith, who has earned 69 international caps for the Springboks, was a member of the South African 2009 World Cup winning squad.
South Africa begin their defence of the World Cup against Wales in Wellington on Sunday, September 11.