Springbok Sevens stalwart Stephan Dippenaar was ruled out of next weekend's Nelson Mandela Bay Sevens tournament in Port Elizabeth with a hamstring injury.
Dippenaar, whose replacement will be named on Tuesday, was one of three South African players injured in Dubai while taking part in Round Two of the HSBC Sevens World Series. South Africa lost only one match during the two-day event, on Saturday in the final against Fiji.
Dippenaar and Jamba Ulengo (foot injury) were ruled out of action on Saturday while Horne sustained a leg injury in their 26-12 semi-final victory over England.
On Sunday, Neil Powell, the Springbok Sevens coach, said a replacement for Dippenaar will join the squad on Tuesday in PE.
"We have players in mind but will announce that on Tuesday morning. Stephan and Jamba flew back to Cape Town already (on Sunday) where they will both see specialists."
Powell indicated there is a possibility that Ulengo might still be able to play in PE. "We believe Jamba has a 50/50 chance to play, but we will not take any chances. Frankie took a knock on his leg and we will see how he reacts to treatment before making any decision," he added.
Powell, in his first season as head coach of the Springbok Sevens since taking over from long-serving Paul Treu, led the team to his first Cup final in only his second World Series tournament since taking charge. South Africa lost 29-17 against Fiji who captured their first Dubai title.
Fiji jumped to second place on the table and they now have 35 points, just four behind World Series leaders New Zealand (39), with South Africa (34) and England (32) within striking distance heading to Port Elizabeth next weekend.
South Africa and the 15 other international teams arrive in Port Elizabeth on Monday evening.
Meanwhile the tournament hosts were drawn in Pool B alongside Kenya, Canada and Spain for next weekend's tournament.