The Tottenham superstar, who scored a double in the 2-1 Group A win over the Scots in Cardiff in October, missed training all week with a virus and an ankle injury and travelled to Glasgow separately from the Welsh squad.
His "modified" and truncated training session at a freezing Hampden tonight included some free-kick practice on his own.
Coleman claimed Bale had "a very good chance" of playing before saying: "I am not the type of manager to play mind games. I would rather get on with it.
"It is what it is. I don't have an elaborate plan up my sleeve; he is not going to play tomorrow or he definitely is.
"It is pointless bringing him up if I didn't think he had a very good chance.
"The medical team are happy with his response, he is better today than yesterday.
"I think the ankle is okay, that wasn't such a big concern.
"Gareth had a bit of a virus on Tuesday and Wednesday so we couldn't do any sessions with us.
"He needed a bit of a rest but he took a later flight because he wanted to be separated from the lads for obvious reasons but he is up and hopefully he will be ready tomorrow.
"If there are any doubts about him then he won't play because we can't take the risk with Gareth or any players because they don't belong to us, they belong to the clubs.
"You have to be selfish because he can make a difference to any team and then I've got to think long-term and if I did that and anything happened - God forbid- and he went back to Tottenham not fit, if I was Andre Villas-Boas I would be thinking twice about the next time.
"So we have to respect that and think long term.
"So unless he is 100 per cent right we can't take the risk and we won't - but at the moment we are optimistic."
The former Wales defender admits he is looking for a strong performance from French referee Antony Gautier in the wake of Dundee manager John Brown's comments about the way to deal with Bale.
In an interview the former Rangers defender, 51, said the star forward "can't run without legs" and although he later said "what I'm saying is get close to him and don't give him time and space" he was again asked if he was advocating physical tactics and replied: "Aye, well I might have been." "I am happy if they want to do that. I would be happy to pay against 10 or nine men," said the former Fulham boss.
"In the first game there was no nonsense and I can't remember any nasty challenges.
"This is a typical British derby game so there will be challenges.
"It might get a little but heavy but that's one thing, but going out and trying to snap someone's legs, break someone's legs, if someone is insinuating that is the way to go about it, I have no respect for that.
"That's not the way to go about winning a football match or stop another player.
"We used to say in the first 10 minutes, give someone a reducer and put him on his backside, that didn't mean break his legs, that's two different things.
"I'm sure the referee will do his job properly."
Comments from former players from both countries have been flying around this week but Coleman distanced himself from former Wales midfielder Mickey Thomas' assertion that this was the worst Scotland team ever.
Asked if Thomas had done Wales any favours with the comment, he said: "No, he didn't - but that is up to Mickey.
"It is a big statement to make. I know Mickey, he is a good fella and paid to give his opinion, but I would disagree with that.
"Most of the Scotland players play top level football. What are we judging it by, Kenny Dalglish, Graeme Souness?
"There haven't been players like that for a long time but they are still a good team, they have a new manager and a good manager and they will have that bit of momentum."
Coleman laughed when asked about former Wales keeper Neville Southall, who said the knives would be out for him if he lost to Scotland.
"I don't know where Neville has been for 12 months, it has been like that for every game to be honest," he said.
"I don't look at it like that. I do feel the pressure but not because I am going to lose my job, I feel the pressure because I want to win."