Cameron Munster's star turn at fullback is expected to only be a cameo following injury to Melbourne halfback Jahrome Hughes.
Munster almost single-handedly dragged the Storm to their 32-14 NRL win over Gold Coast on Friday night in Melbourne, bagging a hat-trick of tries.
But the win was tempered by Hughes's shoulder injury, which meant he didn't return after halftime.
Storm medical staff believe he temporarily dislocated it while making a tackle.
The club said he would go for a scan late on Saturday with the results known on Sunday.
"He's going to be hard to replace if he is out for the rest of the year," coach Craig Bellamy said of Hughes.
"We're trying to stay positive until we hear bad news ... hopefully he might miss a couple of weeks."
Munster started his career at fullback and played two solid seasons there in 2015 and 2016 but began his transition into a five-eighth the following season.
His last start at fullback was round one in 2018.
With Ryan Papenhuyzen a lock at the back, Munster has been more valuable in the No.6 jersey.
But with Papenhuyzen and his replacement Nick Meaney both injured Bellamy turned to the Queensland Origin playmaker, who appeared to relish the extra space.
While delighted with Munster's performance, Bellamy said he was likely to return to the halves for Thursday's clash with premiers Penrith.
"I'm thinking it will be a one-off as we need him in the halves probably more than fullback," Bellamy said.
"We all know what he can do when he gets some space and he likes playing there to honest but I think with Hughesy's injury we might need him in the halves."
Bellamy was also happy with youngster Tyran Wishart, who replaced Hughes despite not training in the halves.
"I thought Wishy (Wishart) did a great job defensively," he said. "He's a tough rooster like his old man (Rod Wishart).
"If Hughesy is out we can train him in there and he can get a bit of combination with that right side."
Cooper Johns started at five-eighth in place of Munster and earned high praise from the coach, who said it was his best performance in his eighth game in Storm colours.
"He did a great job - David Fifita put a target on his forehead and ran at him all night," Bellamy said.
Wests Tigers mid-season recruit David Nofoaluma made an immediate impact and the winger narrowly missed scoring a try on debut for his new club.
"He's added a lot of energy this week - he's been tremendous," Bellamy said.
"I just wanted him to go out there and play to his strengths and back himself, and he doesn't have any trouble doing that.
"It was great to have him out there."
