The Lions' 19-28 loss to the to the Hurricanes had come at a cost for the Springboks.
Malcolm Marx, rated as the premier hooker in the world, is doubtful for the June Internationals.
It was confirmed that Marx will return home on Monday, to undergo scans to the groin injury he suffered.
The injury blow comes less than a month out from the first Test under new Bok coach Rassie Erasmus - when South Africa take on Wales in Washington, America, on June 2.
Lions coach Eugene Eloff said they can only determine how long the burly hooker will be sidelined once he had undergone the scans back in Johannesburg.
The Lions are not flying in a replacement for Marx, as they prepare to take on the Highlanders next Saturday (May 12) in the final tour match.
Robbie Coetzee is then only recognised hooker, but loose forward Marnus Schoeman will serve as cover at No.2 in the encounter with the Highlanders in Dunedin.
"It was a massive setback for us, to lose a player of Marx's quality so early in the match," the coach, De Bruin, said.
The Lions won their first match on tour, beating the Waratahs 29-0.
However, they have been pitiful in the next two matches - losing to a poor Reds outfit last week and the Hurricanes on Saturday.
Ben Lam bagged a hat-trick as the Hurricanes downed the Lions 28-19.
The Hurricanes' victory put them two points behind the Crusaders in the New Zealand conference, but with a game in hand, while the Lions remain top of the South African conference - despite having suffered their fifth loss of the season.