Victor Matfield has been ruled out of South Africa's opening Rugby Championship match against Argentina. Photo: Steve Haag

Johannesburg - Springbok lock Victor Matfield was on Tuesday ruled out of South Africa's opening Rugby Championship match against Argentina in Pretoria next Saturday, due to a knee injury, the SA Rugby Union (Saru) announced.

“Victor's injury will initially be treated conservatively and a decision on his further participation in the competition will be made during the course of next week,” Springbok team doctor Craig Roberts said in a statement.

Matfield suffered from a small tear in a cartilage after being sent for scans on Tuesday morning, following some discomfort in his knee at training on Monday.

The other injury concern at this stage in the Springbok squad is captain Jean de Villiers, who is returning from a knee injury he sustained during Super Rugby in May.

“We'll only know at a later stage if Jean will be ready to face Argentina next week in Pretoria,” said Springbok coach Heyneke Meyer.

“In Victor's case, we will have to call up a short-term replacement, which we'll announce as soon as possible.

“Jean is our captain and one of the most experienced players in the squad. We'll give him as much time as possible to recover, however, a replacement cover can be called up if he is ruled out of the Test at Loftus Versfeld.”

Meanwhile, Eben Etzebeth and Frans Malherbe have been released to play for Western Province in the opening round of the Currie Cup on Friday evening.

Both players returned from long-term injuries and will be allowed some game-time for Province to ease them back into the game.

Etzebeth's last game was in November 2013 for the Springboks against France in Paris, where he picked up a foot injury.

Malherbe has been out for more than three months with concussion.

“Following medical assessments and consultation between our medical team and those of the various provinces, it was decided to release Eben and Frans for this weekend,” Meyer added.

“The provincial CEOs have all been part of the discussions on how to best manage our players and relating to the way in which injured players will return to the playing field.

“In the cases of Eben and Frans, who both have been out for extended periods of time, the Springboks' and Western Province's medical teams decided that the best course of action would be for them to get some game-time this weekend.”

Etzebeth and Malherbe, who have taken a full part in Springbok training since Monday afternoon, will join Western Province on Thursday.