Cronulla co-captain Paul Gallen will miss up to six weeks of football after suffering a knee injury in his side's 40-20 loss to St George Illawarra on Friday night.
Scans revealed the 36-year-old suffered a grade two medial ligament tear during the game, and was one of four forwards ravaged by injury during the game.
Andrew Fifita (knee), Luke Lewis (knee) and Wade Graham (hamstring) all sustained knocks against the Dragons, with Lewis and Graham both in doubt for Cronulla's clash with the Panthers on Friday.
Fifita was worried his season was over after fearing he had torn his anterior cruciate ligament, although the forward confirmed on Sunday he hadn't ruptured ACL, and will now only spend weeks on the sidelines.
If Lewis and Graham can't get up for Friday night's fixture against Penrith, Cronulla coach Shane Flanagan will be without four of his side's best forwards.
Scott Sorensen and Jack Williams could be called in to the 17 for this weekend's match, given they were named as the back-up forwards ahead of the Dragons game.