KNIGHTS forward Aidan Guerra is no sure thing to play again this season after undergoing surgery to repair a dislocated and fractured ankle on Monday afternoon.
Guerra was taken from the field on a medi-cab during the second half of Saturday's 26-18 loss to Manly at McDonald Jones Stadium, and the club said in a statement on Monday that he would be sidelined for "an extended period".
It is understood the minimum recovery time frame will be three months and it could take twice that long before he is fit to resume playing.
Guerra's teammate Jacob Saifiti returned to action last weekend, more than four months after suffering a fractured leg in an off-field incident.
The Newcastle Jets' marquee midfielder, Ronny Vargas, suffered a fractured and disclocated ankle last season and missed five months of football.
Former Knights Cameron Ciraldo (2009) and Daniel Abraham (2005) both took more than 12 months to return to first grade after suffering broken ankles during their playing careers.
Given that the play-offs kick off in five months, Guerra's hopes of being involved, should Newcastle qualify, would appear line-ball.
It is a cruel setback for the 31-year-old back-rower, who did not miss a game for the Knights last season.
In the absence of Guerra, Newcastle will be hoping hard-hitting Sione Mata'utia will be cleared to return from a shoulder injury that caused him to miss the Manly game.
Newcastle's head of physical performance, Balin Cupples, said Mata'utia was "making steady progress" and would return either this week or next.
Skipper Mitchell Pearce, who was replaced after suffering concussion against Manly, is expected to take his place against the Titans, but utility Kurt Mann is likely to miss his second consecutive game with a sternum injury.
Gold Coast, who opened their account with a 30-24 win against Penrith last week, have personnel issues of their own.
Playmaker AJ Brimson broke a thumb against the Panthers and is unavailable, while halfback Ash Taylor is in doubt with a knee injury.
Former Melbourne utility Ryley Jacks is the likely candidate to fill the breach.
Queensland Origin prop Jarrod Wallace has also been ruled out after being suspended for two games for a shoulder charge on Penrith's Dallin Watene-Zalezniak.
Meanwhile, Manly prop Addin Fonua-Blake will appear before the judiciary on Tuesday night in an attempt to avoid suspension for the high shot that knocked Pearce out of Saturday's game.
Fonua-Blake was charged with a careless high tackle (grade one), and could have acceped a one-game suspension either if he took the early guilty plea.
Instead the Sea Eagles enforcer will risk a two-game ban. He presumably intends to argue that Pearce was falling in the tackle.