Huggins last played for Sunderland in September last year, before suffering a stress fracture of the back.
His recovery from that serious injury was then badly setback when he suffered stress fractures in both of his heels. While Neil is hopeful that the 21-year-old has now overcome those significant hurdles in his recovery, the full back now has a lot of work to do in getting fully up to speed.
"Niall has still got a lot of work to do to get back to where we'd like to be to be potentially involved," Neil said.
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"He's been really unfortunate with the injuries that have come along, and during his rehab he's had a few setbacks.
"We're hoping now that we've got him to the point where he's got that clean bill of health so he can start to build his rehab up.
"So there's been a lot of work going into that process over the last month or two to get into that position."
Neil will be selecting from a similar squad for the trip to Bristol City this weekend, though Leon Dajaku is back in contention.
"Leon trained on the Thursday and the Saturday, so he'd only done a couple of days before Coventry," Neil said.
"And unlike the other lads, he didn't get 90 minutes in one of the two previous friendlies. That put him a little bit behind behind the curve.
"But he's trained this week, equally so have the other lads. So we'll see where we go for tomorrow."