All Black Shannon Frizell and Ireland centurion Cian Healy have been confirmed as the latest names to join up with the Barbarians to face the Springboks in June.
The United Rugby Championship playoffs are now confirmed, with eight teams from across Ireland, South Africa, Scotland and Wales all locked in for the quarterfinals on 30 and 31 May.
Bulls head coach Jake White hailed the defensive grit and will to win of his team as they hung on for a valuable 16-13 win over Munster in Ireland on Saturday.
Paul O'Connell will take charge of Ireland for an interim period after Simon Easterby was drafted into Andy Farrell's British and Irish Lions coaching staff.
A 30-man Stormers squad left Cape Town on Tuesday for a vital two-match United Rugby Championship tour in Wales and Ireland over the next fortnight.
Ireland kept their slim hopes of Six Nations glory alive but were made to sweat before beating Italy 22-17 at the Olympic Stadium in Rome on Saturday.