Burger was withdrawn just prior to their 25-15 loss to the Brumbies at the weekend with a torn quad muscle.
“It’s always a big loss losing a player at the 11th hour – especially someone of Schalk’s calibre,” said Stormers coach Allister Coetzee.
“But we’re fortunate to be able to call upon someone like Siya Kolisi, who is of course a Springbok himself, and then there’s also a quality player like Nizaam Carr in the mix too.”
After three straight losses on tour the Stormers will have to beat the Reds this weekend in order not to return home empty-handed.
Coetzee confirmed that Kolisi (who took a slight knock to his head) and fullback Gio Aplon (knee) would be fit for the Reds match.
“Schalk will head home,” added Coetzee, “and we will call up a lock replacement as Jurie van Vuuren, who made his Super Rugby today (Saturday), is (first and foremost) a flanker and can provide additional loose forward cover”.
Captain Jean de Villiers said he believed the team lost focus towards the end of the game having trailed just 18-15 before a controversial penalty try put the result beyond doubt.
“There was definitely a lack of composure by some players and we can’t go on making the same mistakes week in and week out,” he said.
“We will have to sit down and carefully think where we can change things as we simply can’t carry on the way we have until now.”