Siosifa Talakai is set to be ruled out of Saturday evening's crunch semi-final with the South Sydney Rabbitohs, while opposition centre Campbell Graham is said to need a pain killing injection to be able to play.

Talakai has been battling injuries in recent weeks, although managed to play in each of the last two rounds of the regular season, before backing up against the North Queensland Cowboys in last week's qualifying final, which lasted for a staggering 93 minutes.

The centre was racing the clock originally to play the Cowboys after a Mat Croker hip drop tackle ended his afternoon with just two minutes to play in the final round against the Knights.

While it's not believed that tackle is what has caused his latest problem, coach Craig Fitzgibbon confirmed before training on Friday that he was struggling with a shoulder and ankle problem.

The Sydney Morning Herald are now reporting that he is out of the side to play the Rabbitohs, and with Matt Ikuvalu also out for the season, that creates a vacuum in the centres for the Sharks.

Lachlan Miller is the most likely replacement for the Sharks, although it's tipped that Connor Tracey will move into the centres, with Miller to play on the wing.

South Sydney have their own headache ahead of the clash, having beat the Roosters last week.

While Thomas Burgess is out suspended, it's understood Campbell Graham will require a pain killing injection to play, and is no certainty to do so.

He is managing a shoulder injury and like Talakai, has spent time on the sidelines injured throughout the course of the season.

Coach Jason Demetriou insisted he is fine to play.

“He’s fine, he’ll get a needle tomorrow but he’s tough as nails,” Demetriou said on Friday.

“He’ll be right to go tomorrow night.”

Should he miss out on the game, it's likely Jaxson Paulo will come straight into the starting side although could be used on the wing with Taane Milne, who himself narrowly avoided a suspension, shifting into the centres.