Former heavyweight champions Evander Holyfield and Ray Mercer are expected to be in South Africa in February next year.
Showpony Promotions have organised a boxing tribute to former president Nelson Mandela and the two Americans are on the list of celebrities.
The idea is for the 49-year-old Holyfield and the 51-year-old Mercer to meet in a four-round exhibition match. The 40-year-old WBF champion Michael Grant could also be involved in an exhibition.
The event will be held on February 2, the date on which Mandela was released from Robben Island.
Showpony CEO Damian Michael said on Friday the boxing and entertainment spectacular would feature Holyfield, who won five heavyweight title fights.
New Zealand rugby star Sonny Bill Williams, who is also a professional boxer, and several international entertainment personalities have been invited to "The Rumble on the Rock".
The event will, however, not be held on Robben Island, where no suitable facilities exist. There is also no certainty yet that it will be held in Cape Town.
"I am negotiating with a number of organisations to find the most suitable venue," Michael said.
"Cape Town has certain advantages because of its proximity to Robben Island, but I'm also considering the Johannesburg area where."
Irrespective of the venue, the weigh-in will be held on Robben Island. "I've already spoken to the ANC about this," added Michael, "and they are enthusiastic about the idea."
Michael said there would also be serious boxing. He has contracted England’s Matthew Hatton to fight an opponent who will be named later.
A number of leading SA would also participate, he added. The final programme and venue will be announced in September.