Former Argentina captain Agustin Pichot announced his retirement from international rugby after realising he was in no shape to play South Africa next month.

Pichot, the Pumas' skipper since the 2003 World Cup, last played for Argentina at last year's World Cup when he led it from scrumhalf to a best-ever third-place finish in France.

Pumas coach Santiago Phelan offered 33-year-old Pichot a farewell Test against the world champion Springboks in a match celebrating Nelson Mandela's 90th birthday at Johannesburg on August 9.

Pichot admitted he had illusions of playing for sentimental reasons, then realised weeks after finishing his season at Racing Metro in Paris that "I was not going to be right."

"To play for Argentina you have to be 100 per cent physically and mentally," he said. "It would have been disrespectful to the shirt to carry on."

Pichot played 72 Tests since his debut against Australia in 1995, when he scored a try.

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