Manly's crucial win over the Raiders has come at a cost, with an arm break putting second row player Joel Thompson's season in doubt.
The 31-year-old faces a race against the clock to feature in his side's finals campaign, with the club's website reporting that he is expected to be sidelined for four to six weeks.
In better news for Manly, centre Moses Suli is expected to miss only one week, with the club website reporting that the 21-year-old has escaped a serious syndesmosis injury after initial fears were dire.
The Sea Eagles, currently in fourth place, are locked in a heated battle with the Raiders, Rabbitohs and Eels for a double chance in the finals.
The Sea Eagles will face a stern test on Saturday when they host the top-of-the-table Storm at Lottoland.