Keary suffers broken jaw at Roosters training

The Sydney Roosters have suffered a blow as the club gears up for the pre-season trials with five-eighth Luke Keary suffering a broken jaw in a training mishap.

Keary, who will turn 26 on Saturday, was hoping to use the trials against the Penrith Panthers on February 17 and the Manly Sea Eagles a week later, to strike up a combination with his new scrum-base partner, former Melbourne Storm halfback Cooper Cronk.

However, he is now in doubt for the Roosters' round-one clash with the Wests Tigers at ANZ Stadium on March 10 but club officials believe the injury will only put him out of action for four weeks and they are hopeful of him lining up for the season opener.

A club spokeswoman said the incident occurred during "a physical field session". He had a plate inserted in his jaw but "should be fine for round one".

With their first-choice pivot sidelined, Roosters coach Trent Robinson would be likely to switch utility Ryan Matterson into the No.6 jersey while young gun Lachlan Lam is also a chance of breaking into the NRL ranks.

Cronk is part of a new-look spine for the Tricolours with fellow representative star James Tedesco joining the club at fullback while club stalwart Jake Friend will again line up at hooker.

Earlier on Wednesday, assistant coach Jason Taylor told RoostersTV the new duo had made seamless transitions into the squad during off-season training. 

"They’re going really well," he said about their combination with the rest of the spine.

"Both of those guys have been standouts in the way they’ve trained and the way they’ve executed on what we’ve been working on.

"Cooper has really settled in well, really controlling things and taking control of the team."