Johannesburg - Rookies Tucker Vorster and Japie De Klerk, who jetted into Moscow with the rest of South Africa's Davis Cup squad, were excited at the prospect of making their debuts for the national team.
The tie, to be played in Moscow from October 25-27, was a huge challenge for South Africa.
They must beat Russia to remain in the Euro/Africa Group 1.
Tucker then turned professional and had enjoyed steady success on the Futures Tour.
De Klerk, like Vorster, was one of South Africa's most successful junior players.
De Klerk, from Ashton in the Western Cape, went to school in Stellenbosch.
"Tucker has been knocking on the Davis Cup door for some time.
South Africa have approved the late change of venue.
Russia: Alex Bogomolov Jr, Andrey Kuznetsov, Karen Khachanov, Konstantin Kravchuk;
South Africa: Dean O'Brien, Tucker Vorster, Jacob (Japie) De Klerk, Raven Klaasen;
Captain: John-Laffnie de Jager.