Update 7.38pm: Jamison Gibson-Park and Isa Nacewa are set to miss Leinster's Pro 14 encounters against Southern Kings and Cheetahs after the pair were denied entry to South Africa.
The players, both New Zealand passport holders, are without the required visas.
"Leinster Rugby can confirm that both Jamison Gibson-Park and Isa Nacewa have not been granted a visa at this point in time and will as a result return to Dublin at the earliest opportunity," a team statement read.
"Nick McCarthy has been called up to the touring squad as a result and will arrive tomorrow.
"Leinster Rugby will be making no further comment on this matter."
Leinster duo Isa Nacewa and Jamison Gibson Park have been denied entry to South Africa.
Both players are New Zealand passport holders, but have been held at OR Tambo Airport near Johannesburg since this morning as they are without the required visas.
Nacewa and Gibson Park are part of a 28-man squad that's travelled to South Africa for Pro 14 encounters with both Southern Kings and Cheetahs.
Efforts to resolve the issues are ongoing.