Joe Rankin-Costello faces up to 10 weeks on the sidelines with a hamstring injury – with Tony Mowbray hoping to use that time to get to the bottom of the 21-year-old’s muscle issues.

Rankin-Costello has had three separate hamstring injuries since the re-start in June, but has developed into an important member of the squad, not least because of his versatility.

He has started nine matches, in four different positions, but will now miss a significant portion of the season following the results of his scan.

“It’s not a couple of weeks,” Mowbray said. “It’s not a light hamstring injury, it’s quite a severe hamstring injury. We are really sad for Joe.

“It’s more of a 8-10 week injury, it’s a big blow for him and for us.

“But it gives us all an opportunity to build a programme that will make him a more robust footballer so that when he moves on in his career he can sustain a lot more games back-to-back and he can keep playing at the levels and the intensity that he’s been at.

“Every game he produces really high numbers, particularly when he plays full back, he’s doing a lot of high intensity running and a lot of thought will go into making this hopefully the last hamstring injury he has for a very long time.

“We spent two hours with the medical department, the strength and condition department, sports scientists, because we need to get to the bottom of these muscle injuries.

“I fully understand the level of training and the numbers have gone up dramatically from what the norm would be.

“People have to be ready to play so we have to get their bodies robust and they have to work, whether that be on the grass or in the gym, because we can’t have players breaking down.

“Joe has had a few hamstring injuries and we need to get to the bottom of that and that work is progressing and I’m sure we will.”

Mowbray reported positive news on Liverpool loanee Harvey Elliott who limped out of the win at Preston North End.

The early indications proved correct in that it was a bruised knee that forced him off at Deepdale, but Mowbray says he will be in contention to return to the starting line-up against Barnsley at Ewood Park this weekend.

“He just felt a bit shocked I think,” Mowbray explained. “His knee was pretty painful at the time, but he’s trained today, he’s got a bruise at the top of his knee, bottom of his thigh, and he’ll be available for selection.”

Daniel Ayala has also trained, and while this weekend will come too soon for the Spaniard who has spent the last month on the sidelines with a groin problem, the central defender is nearing being able to return to the first-team picture.

Derrick Williams is set to return to training next week, while Bradley Dack is also set to boost his training levels in the coming days after a slight setback with a hamstring issue.

Bradley Johnson will return from a one-match ban, having missed the North End win after picking up a fifth booking of the season against Luton Town, in a boost to the manager’s options.