Blackburn Rovers will be without Sam Gallagher for at least six weeks after he came off injured against Middlesbrough.

Jon Dahl Tomasson had initially hoped the striker would be ok despite picking up the injury at the weekend. Gallagher was replaced on the hour by Semir Telalovic after he went down for treatment.

However, it's now been concluded that the injury is worse than first feared and he will be sidelined until November. It's a major blow for Rovers and Gallagher, who had looked bright in his last two starts after missing the beginning of the season with another knock.

"[Sam] Gallagher is injured, I was surprised that he will take 5/6/7 weeks when we got the scan yesterday," Tomasson told RoversTV. "I'm really disappointed for him and the team. 

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"Sam has been injured a lot, he’s an important player. I feel sorry for the boy, he's a great lad with great mentality and a great attitude. But we can't change it."

He added: "We have to look at the options we have. Semir [Telalovic] has just arrived, [Tyrhys] Dolan has played in that position before, [Harry] Leonard can play there, [Sam] Szmodics has played as a false 9, [Ryan] Hedges can play there. We've got options."

Gallagher's injury means Telalovic could be handed his first Championship start against Sunderland on Wednesday night. Harry Leonard, who started the first three league games of the season, is another alternative with Niall Ennis still out. Tyrhys Dolan, Sam Szmodics and Ryan Hedges all featured as false nines too at various stages last year.

There is better news on Lewis Travis, who also went off against Middlesbrough. The captain should be fit to keep his 100 per cent record of starting in the league this year.

"We know that [Lewis] Travis is a warrior, he’s tough, I think he’ll be alright for tomorrow," he said. [Niall] Ennis is still out, he will be training this week. [Jake] Batty will get minutes against Hertha (Berling) tomorrow (Wednesday)."

Sunderland arrive at Ewood Park in good form themselves, having beaten Queens Park Rangers 3-1 at the weekend. That followed a 5-0 drubbing of Southampton before the international break.

It's expected to be an open, entertaining match at Ewood Park with plenty of narrative surrounding the fixture. Tony Mowbray is back at Rovers for the second time whilst Bradley Dack returns for the first time since he was released in the summer.

Tomasson is wary of the danger posed by Sunderland, who are particularly potent on the counterattack. He is excited for what should be a fascinating contest.

 "They are a good team with individual quality," Tomasson said. "A lot of technical players who are good with ball, who like to dribble one against one. We are more or less level in the league like we were last season. It's going to be a great game."

"We all know the quality of Dacky," he added. "He was an excellent player for Rovers, who came back after two terrible injuries. He was very important for us in December to January last season before he got injured again."