Danny Jordaan, the 2010 South Africa World Cup supremo, said the future use of two stadiums built specially for the tournament hinged on their also becoming rugby union grounds.
"We need to make the stadiums viable...The central issue is whether rugby will move to the new stadiums. I think they will.
"Their stadiums were built in the 1950s," Jordaan, speaking in London, said on Thursday.
Durban's Moses Mabhida Stadium, which has been built at a cost of R3.1 billion ($413 million) is right next door to the Kings Park home of the Sharks Super 14 rugby union team.
But the Sharks are so far showing no inclination to move, sparking fears the Mabhida Stadium may be unviable economically once the World Cup is over, leaving the city with an expensive white elephant.
There are similar concerns in Cape Town, where a new stadium in Green Point has cost an estimated R1 billion more than its Durban counterpart.
But the Stormers play at the Newlands ground, the home of rugby in Cape Town for over a hundred years, and the Western Province Rugby Union has maintained that is where the team will be staying after the football World Cup.
"These are emotional debates," Jordaan said. "The debate about the 'new' Wembley took five years in London.
