South Sydney have suffered a double injury blow, with James Roberts and Ethan Lowe both going down in the club's loss to Newcastle last weekend.
Roberts will surgery for a right pectoral rupture, likely ruling him out for three three months of action.
He now faces a battle to be fit for the finals series.
Lowe suffered an exacerbation if an old neck injury he previously had an operation on in 2016. He will see a specialist to plan the road ahead.
The Rabbitohs said in a club statement that it is too early to put a timeline Lowe's potential return.