Jon Dahl Tomasson believes Sam Gallagher's fitness issues could be down to a high level of work rate.

The Blackburn Rovers forward is facing six weeks on the sidelines after suffering a calf injury against Middlesbrough. The problem is worse than first feared and it's now unlikely the forward will feature before November.

Gallagher has suffered with injuries, particularly muscular, during his time at Rovers. Since Tomasson became the head coach, he has only played the full 90 minutes on 10 occasions.

Equally, Rovers' record with Gallagher in the team is far better than when he is absent. This latest blow adds extra pressure on Semir Telalovic and Harry Leonard to lead the line, with Naill Ennis also on the sidelines.

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When asked about the 28-year-old's fitness record, Tomasson pointed to Gallagher's his volume of work rate. He states that under his reign and before, the striker gets through an incredible amount of work.

"We all know Sam had a bad history (with injuries) before I arrived," he said. "When I arrived as well, he has got injured.

"He has an extremely high output in every game if you compare it to a lot of other players. I think that is one of the things that is extreme, not just in my time but before I arrived.

"It is disappointing for us as a team but especially for the boy. He is a good lad, he has a great mentality and a great attitude. We can't change it.

"I am always disappointed when a player gets injured. He is extremely disappointed, we need all the players, we don't have the biggest squad so we need everyone fit."

Tomasson is hopeful that Ennis will be back on the training pitches next week, though he will still need some time to get to match speed.