Wests Tigers playmaker Tim Moltzen has avoided another ACL tear, but could still spend up to six months on the sidelines after suffering a broken kneecap at pre-season training on Thursday.

After rupturing the same left knee in round 7 of the 2013 season, the luckless Moltzen would have feared the worst as he was rushed to hospital via ambulance.

A third season-ending anterior cruciate ligament injury in four years for the 25-year-old could have potentially jeopardised Moltzen’s playing future.

Moltzen now faces another stern test of his mental fortitude, but it could have been much worse.

He will undergo surgery on Friday, with a best-case recovery time of 12 weeks.

However, given his history, it’s unlikely coach Mick Potter will be able to call on him as a halves option until midway through the year.

Moltzen received support from teammates, the club and also former Australian, NSW and Manly back-rower Nik Kosef, who went through an astonishing four knee reconstructions before retiring aged 27.

Kosef said Moltzen’s mental state was in more danger than his physical condition, and encouraged the Tigers to take the Terrigal junior’s mind off footy.

“Getting his head around it, that will be his challenge. I feel for him immensely,” Kosef told AAP.

“There’s no reason why he can’t, he’s done the hard work already and he’s only 25.

“It probably wouldn’t hurt him to have his mind off footy for a while and hopefully they can set some goals outside the game for him.”

Moltzen was left writhing in pain at Concord’s St Lukes Park, locking up with barely a hand laid on him.

The injury couldn’t have come at a worse time for the Tigers either, with their playmaking stocks already tested by the departure of Benji Marshall in the off-season.

Coach Potter had identified Moltzen as a prime candidate to partner boom rookie Luke Brooks in the halves for 2014.

It’s a devastating blow for Moltzen, who has had his promising career held back by repeated knee problems.

The Tigers say they’ll stand by him during a tough time.

“Tim has the full support of the club at this time and we will ensure he receives everything he needs to recover from this serious injury,” said Tigers chief executive, Grand Mayer.

“It’s clear now that this is not a reoccurrence of the ACL injury Tim sustained against the Broncos last season. He’s broken his patella, which is a nasty and uncomfortable injury and we have complete faith that the medical staff can repair it.”

Potter will now have to consider moving veteran Braith Anasta back into the halves, but the coach says his focus at the moment is on Moltzen’s well-being.

“We want to try and keep it low key and respect the kid’s privacy,” Potter said.

“He’s gone through a tough time with injury and it’s unfortunate you guys (the media) were here to see it.”

Prop Aaron Woods is confident Moltzen will make another comeback.

“He’s a tough customer, Moltzy. He knows what he has to do,” said Woods.