BRENDAN RODGERS has expressed his dismay after learning that Reo Hatate will be out of action until after Christmas, and has vowed to get to the bottom of the midfielder’s injury problems.

Hatate limped off in the early stages of Celtic’s Champions League tie against Atletico Madrid last Wednesday, and it has since transpired that he suffered a grade four hamstring injury.

The Japanese travelled to London yesterday for further tests, but while it is still unclear exactly how long he will be sidelined, Rodgers is resigned to being without one of his star men for at least a couple of months.

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The hamstring Hatate has injured is not the same one he tore last season, but after also missing matches at the start of this campaign with a calf problem, Rodgers is looking to ascertain if there are underlying issues in his routine or his training program that are making him more susceptible to injury.

“It’s certainly going to be after Christmas before he’s back, which is really disappointing for him and for us,” Rodgers said.

“Without knowing exactly, it’s definitely going to be after Christmas before he’s back.

“Sometimes the hamstrings can be naughty, so it’s just a shame for him. It wasn’t great news, it was a stage four level injury, which wasn’t great.

“He had one towards the end of last season on the hamstring on the other side, and he’s had a calf problem earlier this season as well.

“So, this gives us a chance to investigate with him, and run through every fine detail of it, because his calf and hamstring have happened early in the games.

“There’s lots of things that can happen with footballers and how they work, so we’ll look at it and investigate every part of his training program and what he does away from here, and see if we can help and support him.”

Hatate is likely to also be missing for Japan’s matches in the AFC Asian Cup in January.

“He’ll be a big doubt for that,” Rodgers said.

“His season has been broken. As he started to find that rhythm again in his training and getting into the team and looking exactly what I want from him, and then he’s starting perform, to then break down is such a shame for him.

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“And for us, because he’s a very good player.”

There was better news on the injury front for Rodgers around full back Alistair Johnston, who it was feared may have suffered from a concussion in the weekend draw with Hibernian.

“It wasn’t concussion we just wanted to make sure,” he said.

“I didn’t think there was a point in taking a risk when he was not feeling great, and Tony (Ralston) came in and did a good job.”