NSW coach Laurie Daley says Jarrod Mullen’s injury is not only a blow to Newcastle but to the Blues preparations.

NSW coach Laurie Daley says Jarrod Mullen’s expected four-month injury lay-off is a major blow to the Blues’ State of Origin planning.

Mullen finished last season in career best form as the Knights surged into the preliminary finals, but the club’s premiership hopes for this year have been significantly rocked by confirmation the five-eighth has torn his hamstring from the bone.

To go down in the Auckland Nines comes as a devastating setback for Mullen who was finally back in Origin contention after making a solitary appearance in 2007.

Daley expressed shock upon hearing that one of his playmaking options, and one of the best general-play kickers in the game, is already unavailable.

“That’s a big blow, obviously to Newcastle but also to NSW rugby league because … if he started the year off well he certainly would have been someone to keep an eye on,” Daley told AAP.

“He finished last year off strongly. I thought he was composed, in control of his game and looked like he was confident in everything he was doing.

“We’ve got some depth in the halves so … we’ll move on.”

Mullen said he was “shattered”, but found a silver lining in the Knights’ announcing gun halfback Tyrone Roberts has re-signed on a two-year deal.

After meeting with a surgeon on Monday, Mullen will find out how long his recovery time will be, but if it’s a complete tear it will be four months.

“It’s either partially or fully torn off. It’s not good news,” Mullen told newcastleknights.com.au.

“I obviously trained hard all off-season so to come up with this is pretty shattering actually.

“Hopefully it’s not as bad as they think and I’m back sooner rather than later.”

Mullen said Super League purchase Michael Dobson would come into contention to replace him – and the former Canberra half will play in the Knights’ trial against the Raiders this weekend – however the club may simply look to move captain Kurt Gidley to the halves.

The plan was to shift Gidley to hooker to fill the void left by Danny Buderus, but his experience may now prove more valuable in the playmaking department.

Either way, 22-year-old Roberts, seen by the Knights as a future leader, is set for a major jump in responsibility

“Tyrone is an outstanding young man and has a wonderful future ahead of him,” said coach Wayne Bennett.

“It has been pleasing to see him grow in confidence.

“Tyrone is one of our key young players who will be a long-term player at the Knights.”

Roberts said he never entertained the thought of leaving.

“I’ve been here since I was 14 and I’ve grown to be part of this club and I’m thankful I can get this over and done with and concentrate on my year this year,” he said.