Terell Thomas is set for a scan on the hamstring injury that looks set to rule him out of action for Carlisle United.

But head coach Mike Williamson is boosted by the return of Aaron Hayden and Georgie Kelly to fitness this weekend.

Defender Thomas will miss the visit of Doncaster Rovers having pulled up injured in the first half of Saint Lucia’s defeat to Curacao this week.

The full extent of the problem will be determined when he returns to Carlisle later this week.

“At the back end of the week we're looking at [seeing him],” said Williamson. “He’s going to have to get scanned to fully assess it, and without speculating on anything we'll just have to wait and see what happens.”

Hayden is back in training after the illness that kept him out of the 1-1 draw at Bromley. Williamson said: “We’ve built him up this week, but he’ll be in full training now, so [there are] issues.”

And striker Kelly could be in the frame to join the matchday squad for the first time under Williamson, after his recovery from a calf injury.

The former Rotherham United man has been out since late August when he was injured in United’s 3-0 defeat to Williamson’s MK Dons.

“Since we've come in, I can see the intensity in his body language, in his vocabulary, in his desire to get back,” said the Blues boss of Kelly.

“I can see that he's really been frustrated with his situation, so we've had to take our time with him.

“Last week he trained really well and this week he's in training.

“We are navigating frozen pitches at the minute, which is not easy, so we've got a few calls to make there, but hopefully he has another clean week and he'll be available for selection.”

Williamson said Kelly’s desire is clear to leave a highly frustrating time with injuries behind him.

“I think he’s just hungry. You can see the appetite he's got, you can see what he's going to bring before he even steps on the pitch,” the United head coach added.

“I think he's really going to help us and take us to the next level as long as we can keep him fit and got to be careful with him.

“Touch wood, he gets no ongoing issues and we can just keep building that and really integrate him back into the team.”

Harrison Biggins is unlikely to return to action this weekendHarrison Biggins is unlikely to return to action this weekend (Image: Ben Holmes)

Midfielder Harrison Biggins, who has a minor knee injury, is unlikely to return in time to face his former club Doncaster on Saturday.

“He’s working hard with Sophie [Birnie, United’s head physio], he's not going to be too long, but it might be a little bit too early for the weekend.”

Winger Jordan Jones is also back on the training pitch and, although he will not return this weekend, he is getting closer to a comeback.

“I am, he is, the whole club are chomping at the bit to get him back, but we've got to make sure it's not too soon,” said Williamson.

“He’s got his training load up this week. He was in the small sided games which was a pleasure to watch.

“We’ve just got to make sure he gets through today, recovers well, and then he’s probably looking at another clean training week before he's available.”

Williamson has midfielder Harrison Neal back from suspension this weekend but defender Ben Barclay will serve a one-game ban.

Carlisle, meanwhile, have delayed training today in the hope they can train on grass, after more freezing overnight conditions.

"We've got a later start today, to just try and give us every chance of the grass being thawed out, because that's optimum for the lads and consistency is really important as well," said Williamson.

"But there's a chance that if it's not fully softened out then we'll have to go on 4G, which means we'll have to compensate for the [training] load with the surface.

"But this is what most teams [have to weigh up], unless you're lucky enough to have those luxury facilities."