The 29-year-old Jane hurt his knee at training on Thursday and had scans on Friday, the Hurricanes said. They would not have any idea on how much time he would need off the field until he had seen a surgeon.
A picture of Jane being helped off the field at Paraparaumu, about 45 kilometres north of New Zealand's capital city was circulated on the micro-blogging website Twitter on Thursday.
Jane, a prolific Twitter user, recirculated the picture but said he "just needed a rest". The Hurricanes confirmed late on Friday that he had torn the ligament, and Jane then also used Twitter to confirm he had "got some bad news".
The winger had only returned to training this week.
"It is devastating for Cory to have suffered this serious injury when he was looking so strong for this season following such a successful 2012," Hurricanes coach Mark Hammett said in a statement.
"We know that CJ is focussed and dedicated to his rehabilitation. So he will be committed to working hard in his recovery to come back better and stronger.
"This is not the news we wanted to hear at the start of the season and we acknowledge the loss of a world-class player.
"However, we have a strong squad for 2013 and CJ's misfortune means its an opportunity for another player to step up."
The Hurricanes play the Canterbury Crusaders in Timaru on Saturday in their first pre-season game, with their first Super Rugby clash against the Auckland Blues in Wellington on Feb. 23.
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