"Scott has been training for an hour-and-a-half - twice every day - and his weight is okay."
"On 9 December, after three or four rounds, Nicky Cook is going to find himself in a place he does not want to be.
The British Boxing Board of Control insists no decisions will be made on his December world title defence until after his prison release.
"Scott is below the weight he would normally be at this time before a fight because obviously he hasn't been able to over-indulge.
BBBC general secretary Simon Block said certain issues needed to be resolved.
If Scott is fit, then the fight will go ahead Promoter Frank Warren
"There are certain questions which must be resolved when he is out," Block said.
"I'm not sure exactly what his diet is but he told me it wasn't the worst food they were giving him. But I am confident he will retain his belt."
"Is he in a fit state to continue his career. If not now, when - if ever?"
Promoter Frank Warren is hoping to get the medical out of the way as soon as possible so he can finally confirm the bill.
Harrison's detention has thrown his 9 December defence against Nicky Cook into doubt.
"It has been an unsatisfactory situation and has not been good for Scott or for the sport," said Warren.
The Cambuslang fighter was due to have undergone a BBBC medical on Monday to determine his fitness for the Cook fight at London's Excel Arena.
"Legally, I am obliged to honour the contract and, providing he is passed fit to fight, then I have to honour that.
But Block maintains there are further hurdles to negotiate before the sport's governing body can sanction the fight.
"We have the right to have him take a medical and he will undertake one with a doctor registered with the BBBC.
"What is essential in the case of Scott Harrison is: 'Is he in or is he out (of prison)?'" Block said.
"It is a sorry state of affairs all round but the prime consideration has to be to Scott's health first and foremost. But, if he is fit, then the fight will go ahead."
"A boxer can prove his fitness at any time but what is relevant is the 9 December situation.
Hughes added that Harrison, 29, declared his gratitude to manager seconds after being released from the Malaga jail.
"It was proposed he defend his championship on that date. There are a number of factors now relating to that.
The Cambuslang fighter had been behind bars since 6 October on an alleged assault charge.
"Firstly, does promoter Frank Warren still want to put the fight on?
Hughes said: "The first thing that Scott did when the doors opened was come over and give me a cuddle.
We spoke to Frank Warren to ensure the fight was still on Barry HughesScott Harrison's manager
"Then he said, 'thanks for standing by me. You always remember the guys that stand by you in the bad times more than the guys who stand by you in the good times'.
"Number two is the question whether he is still champion, because if he is not he will not have a title to defend.
"That made all the hard work and hassle worth while."
"Then, thirdly, if he still wants to box, can he be found fit to fight?
"I certainly do not know the answer to any of those questions at this time."
The World Boxing Organisation had already said the Scot would be stripped of his title.
And Warren himself said: "It is not necessarily the case that the fight is back on.
"Scott has been released from prison and has a contract to fight and we have to honour that contract.
"But it is subject to the fighter passing a medical, so he has to get through those first and he will see a doctor from the BBBC on Monday."
Harrison's manager, however, remains positive that the fight can be put back on track.
"We spoke to Frank Warren to ensure the fight was still on," said Hughes.
"He was more than willing to put the fight back on 9 December."
