Shaun Johnson will miss Cronulla's crucial clash against Manly, with the Sharks sweating on the seriousness of the star half's hamstring injury.
Johnson joined a growing casualty ward after suffering a right hamstring issue in Sunday's scrappy victory over Canterbury.
The Cronulla halfback had put second-rower Briton Nikora through a hole at Cbus Super Stadium before pulling up and then limping from the field.
The Sharks were on Monday battling with the logistics of getting the 30-year-old a scan out of hotel quarantine, but have already conceded he won't face the Sea Eagles on Sunday.
"We just cross our fingers that it's not too bad," Hannay said.
Cronulla were without a host of stars against the Bulldogs, including captain Wade Graham (concussion) and five-eighth Matt Moylan (calf).
First-choice selection Aiden Tolman is suspended until round 20, while experienced pair Will Chambers and Josh Dugan have been unavailable due to COVID-19 protocols.
Neither of the pair are expected to be rushed back against Manly.
The Sharks are precariously placed in seventh spot with six games left in the regular season. Just two points separate them and 11th-placed Newcastle.
"We're starting to get a little bit thin again," Hannay said.
"One of the keys for us when we've turned our season around has just been health, getting our best players out there.
"We got some good talent on the pine again at the moment and it's not ideal."
Johnson has been troubled by hamstring injuries over the past two years and is headed to the Warriors at the end of the season, leaving him with precious few opportunities to steer Cronulla to the finals.
"One thing I know about Shaun is he looks after himself," Hannay said.
"He's a reasonably quick healer.
"I know he'll jump into his recovery and rehab and do everything he can to get back as quick as he can.
"We won't be jumping at shadows.
"We'll assess it, see where it's at and we'll get him back when he's ready."
Moylan could make a welcome return this weekend and is likely to join Braydon Trindall, who has filled in at five-eighth, in the halves.
However, Hannay said the club wouldn't take any risks with the injury-plagued playmaker.
"(Moylan is) running," he said.
"He's got a greater history than Shaun in terms of injury. We are very mindful with Matt's history.
"But if he's right, he'll certainly come straight back in. But we won't be rushing him at the same time."
Australian Associated Press