Rovers manager Tony Mowbray fears Marcus Antonsson could be out of action for "a few weeks", but says he's still waiting to discover the extent of the injury.
The attacker limped off during last week's 2-2 draw against Scunthorpe at Ewood Park, a knock which kept him out of Monday's trip to Rotherham.
Asked about Antonsson after the game, Mowbray said he's hoping to get a better idea of the Swede's condition later this week.
“It is what it is, and sometimes those injuries have to settle down," he told reporters.
"We’ll have to let the swelling go down before we can see what the problem is.
“What we do know is that he’s unavailable at the moment and might be for the next few weeks. Hopefully it’s not too bad but we’ll find out in the next few days."
In Antonsson's absence, Bradley Dack again caught the eye by scoring his 10th goal of the campaign, and Mowbray reserved special praise for the attacker.
“I think we’ve watched Bradley enough now to know that once he’s through he’s going to score," he added.
“He’s a fantastic finisher, as good as we’ve got at the club, so I feel confident when he goes through on goal."
Rovers are next in action on Saturday, when Hull are the visitors to Ewood in the Emirates FA Cup third round.
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