Josh Aloiai revealed he played on for more than 40 minutes and required a pain-killing injection on a busted AC joint in his right shoulder in Manly's win over Gold Coast.
Hurt in the second set of the 26-18 win, Aloiai's injury has left him in severe doubt for the Sea Eagles' Thursday night blockbuster against Cronulla.
One of Manly's most crucial men in the middle, Aloiai was due for scans on Sunday to determine the extent of the injury.
But Sea Eagles officials already have reason to fear the issue is a higher-grade sprain.
The 26-year-old played through a 14-minute stint after sustaining the injury in his first hit-up, before being needled and returning to the field in the second half.
"I knew straight away (what I had done)," Aloiai said.
"I felt it kind of pop and then every time I was running and getting squeezed it was popping on me a little bit.
"(But) the way the game was, I just needed to be out there ... I needed to help."
The prop's shoulder is one of several injury concerns for Manly ahead of the clash between two of the NRL's most in-form teams.
Sean Keppie, Tolutau Koula and Lachlan Croker all suffered head knocks and are in some doubt given the five-day turnaround.
Keppie's is believed to be the most serious, potentially creating another problem for Manly in the middle.
There was better news for Reuben Garrick and Haumole Olakau'atu, who battled through issues on Saturday night that were later revealed to be a knee cork and cramps respectively.
Manly could also have Marty Taupau (neck), Morgan Harper (COVID-19) and Josh Schuster (ankle) back for the clash in Cronulla.
But the absence of Aloiai for any period of time would be significant, given the way he has helped turn Manly's pack around.
While it is possible to continue to be needled up to play through AC sprains, the usual time period out can be anywhere between two-to-six weeks.
Praised during the week for his social media post and stance against postcode warfare, Aloiai's impact has also been large on the field.
Well beaten in the middle in the opening fortnight, he topped Manly's yardage in his first two games back with the Sea Eagles.
And most importantly, he has helped Manly to two straight wins without Tom Trbojevic on a game built around winning the fight rather than last year's flair.
"What we're taking pride in is starting to be one of those real gritty and gusty teams that are happy to grind teams out of games," Aloiai said.
"It's that, rather than just counting on brilliance and finessing teams out of games.
"We don't believe that's what wins comps. We're starting to be very gritty."
