Johannesburg - Bulls utility back Lionel Cronje has been ruled out for the remainder of this season's Super Rugby competition.
The Pretoria union said on Tuesday that Cronje, 22, had picked up a pectoral muscle tear in his chest and would undergo an operation later in the week.
Cronje, who did not turn out for the Bulls in their Super Rugby opener on Friday, injured himself in a pre-season Vodacom Cup friendly against a Sharks XV earlier in the day.
"Lionel will be operated on this week and he will be out of action for at least six months," said Bulls team doctor Org Strauss.
"I cannot see him playing Super Rugby this year."
Cronje had trouble with a knee ligament injury in 2011, when he turned out for the Stormers, which affected his season.
Having recovered from that injury, he was expected to make his Bulls debut in 2012.
"It is a big set-back to us for sure," said Bulls coach Frans Ludeke.
"Lionel was part of our plans and would have been very valuable for our tour to Australasia in a couple of weeks because he is so versatile.
"It is a real pity for Lionel as well, as he has worked really hard to get back to his best following his knee injury."
The Bulls said a squad replacement would be named later if deemed necessary.