Melbourne are sweating on a pectoral injury to skipper Cameron Smith which could rock their NRL premiership push.
The Storm's medical staff fear Smith could miss up to six weeks after aggravating the injury in the team's costly victory over Canberra on Saturday.
Billy Slater is also in serious doubt to face Manly next week after being knocked out by a sickening blow from Raiders forward Sia Soliola minutes after Smith went off.
The Storm are deserved premiership favourites but missing their influential captain for an extended period would be a major blow with the Sea Eagles, North Queensland in Townsville and the second-placed Sydney Roosters among their opponents in the final six weeks of the season.
In his 16th NRL season, Smith is one of the competition's most durable players and has rarely missed games through injury.
He played his 349th game on Saturday, drawing him level with Steve Menzies as the third-most capped player in premiership history.
Terry Lamb (350) and Darren Lockyer (355) are firmly in his sights.
Smith was remaining positive about the severity of the injury after the match.
"We'll get back to Melbourne, have some scans and go from there," he said.
"I think it was just more of a precautionary thing.
"I went out in the second half just to see how it was feeling and it was feeling pretty average.
"The decision was to come off because there's still a long way to go in the season."
Slater was concussed by Soliola's hit, leaving him feeling ill and lying on a bench in the sheds after the game.
"It was a pretty heavy knock," Storm coach Craig Bellamy said.
"He's talking but he's not feeling too good so we'll just have to see how it goes throughout the week.
"For him to get knocked out like that it's pretty severe."
Bellamy was delighted with how his players repelled the Raiders without two of the "big three".
"We had a few other guys that were wounded out there as well so it was a real gutsy performance," he said.
"It certainly wasn't one of our most polished performances but it was gutsy."
