Schmidt looking for 'alpha males' to battle Boks
The Ireland head coach's plans were disrupted with the confirmation that star flyhalf Jonathan Sexton had undergone surgery for a shoulder injury sustained in Leinster's Pro12 Final defeat by Irish rivals Connacht last weekend, and will be out of action for three months.
Sexton's Leinster teammates Luke Fitzgerald (knee ligament), Dave Kearney (groin) and Rob Kearney (hamstring) have also withdrawn from the squad.
Leinster No.10 Ian Madigan, who will join French club Bordeaux-Begles at the end of the tour, has been called up to fill the gap at flyhalf.
It's far from ideal preparation for Ireland as they attempt to earn a first ever Test victory against the Springboks on South African soil, but Schmidt has backed Sexton's understudies to step up to the mark when the series kicks off at Newlands, Cape Town, on June 11.
"It's a 'needs must' situation and one of the things you find when you do lose players who are very dominant in the group other alpha males emerge and they help drive the group," Schmidt insisted.
Ulster's Paddy Jackson is also vying for the flyhalf position with Madigan, who has spent much of the past season with Leinster as deputy to Sexton.
"I've no doubt that Paddy and Ian can both play that role. It is a pivotal position, it's a position where you've got to have some degree of control of the team during training, during the match so that the players know where they're going," said Schmidt.
"The big advantage for Paddy is his form and regular game-time at the end of the season as opposed to Ian who hasn't had that opportunity, but he's trained incredibly well in these two training sessions that we've done.
"Those are the decisions that we'll make at the latest by Thursday, we'll try to give the 10 particularly an indication by Tuesday so that they get enough time in the saddle to really lead the guys around."
Jackson was included in the original squad, at the expense of Madigan, whose international chances will likely diminish when he moves to France's Top 14.
During the Six Nations, Schmidt opted for Madigan over Jackson.
"If it is Jacko it's a real opportunity for him to fill those big boots, that big jersey, but also be himself," Schmidt said.
"I'm not going to ask Paddy Jackson to be anyone other than the player he's comfortable being because that's a good player, that's a player that can be effective at Test level."
Agence France-Presse