Sydney Roosters five-eighth Luke Keary is a doubt for the start of the NRL season after breaking his jaw.
Keary was hurt in a training mishap and has had a plate inserted in his jaw.
The 25-year-old was hoping to use the trials against the Panthers on 17th February and Manly a week later to strike up a combination with his new scrum-base partner, former Melbourne Storm half-back Cooper Cronk.
A spokesman for the Tricolours said Keary would be out of action for around four weeks.
That could have him in contention for the round-one clash with Wests Tigers at ANZ Stadium on 10th March, providing his recovery goes well.
Keary won the 2014 premiership with South Sydney Rabbitohs, before moving to the Tricolours for the start of last season. He played 25 games and scored eight tries in his debut Roosters campaign.
With the 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.
The Tricolours have a new-look spine for 2018 that also features Cronk and fellow representative star James Tedesco at full-back.
Assistant coach Jason Taylor says Cronk and Tedesco have made a seamless transitions into the squad during off-season training.
Asked about their combination with the rest of the spell, Taylor added: "They're going really well. 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."
Sydney are 3.10 to win the NRL Grand Final, while the Roosters are 1.001 to finish in the top four.
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