RONNY DEILA sleeps pretty well these days. There are no long nights for him, lying in bed, staring at the ceiling, his mind full of whether his full-backs are up to it or if the strikers know what is expected of them.

That's at least before games. Even after wins Celtic's manager can be awake for hours, mulling over what has just happened.

A year ago, before Celtic began a European campaign that was as disappointing as it was strange, even if the Inter Milan games were good value, the Norwegian found it difficult to catch a wink. He was new to the job and despite his cool Nordic tendencies, there was worry and amnesia. It's never a good combination.

Now as he looks forward to one of the biggest tests of his entire managerial career, if we are to believe that Qarabag of Azerbaijan are as good as everyone has been telling us, Deila is refreshed, relaxed and confident. Nothing has been left to chance. He knows his team inside and out. After chatting to the man, you come away believing there is utterly no way Celtic are going out at this stage.

“You feel like you’re putting all your energy into the games,” said Deila when asked to describe his emotions. “We’re starting to get some experience of this, switching onto the right things.

“It’s about enjoying the game, looking forward to it and believing what you have done for a long time. That’s important. If you start now to think what you’re doing is not right or you have to change then you’re not a good coach. You have to believe in what you’re doing.

“If I have done the work I should have, then I sleep well. If I feel I am not prepared, then I don’t sleep. I just think of the choices I have to make. That’s why after games I don’t sleep very well. You reflect, you go through the game and you look for answers.

“Am I sleeping better now than 12 months ago? Yes! Definitely. I’m more in control of the situation now but then again it’s a football match. We have to go out, believe in ourselves. They have a lot of quality and they have got a lot of good results the last half-a-year. But if we are at our best, we can cause Inter problems so we can cause Qarabag problems as well.”

Deila will make sure his players and himself find the right place between excitement, tension and relaxation going into the match.

"The biggest challenge is you always want to do too much," said Deila. "Then it’s going to be over-stressed. If you are stressed you do stupid things. It’s the same with the players – if they’re stressed they make silly mistakes. You have to be confident. We know what we’re going to meet, we know we are facing a good team.

“But in the end it’s about what we are doing. It’s about how we cope with their strength. Most of all how we get our strengths into the game. You have to do what you do all the time but you also have to be cautious in small things too.”

There has always been a school of thought that Scottish football fans no matter who they follow are an impatient breed, in stark contrast to our continental cousins. Celtic supporters and teams have been guilty in the past on European nights to want to charge forward when seeing out the game was the trick of the day. That has cost them in the past. Things have changed.

Sure, some early goals against Qarabag would be welcome but there will be moments when the men from Azerbaijan will enjoy possession and Craig Gordon is more than likely to be called into action in Glasgow. Patience, as always, is the key.

“The crowd inside Celtic Park are quite intelligent,” said Deila. “We will play a lot of the same way we normally do but it’s about high pressure, intensity, it’s about getting forward quickly when we get the chance. It is also sometimes, when you meet good opponents, about defending as well.

“We want to be in their half all the time but when you play good teams, then you know you’ll have to defend. The fans can see that. It won’t be a problem.

“We must stick together as a team defensively. When we do that, we don’t concede goals. When we don’t, as we did a little bit against Inter at home when we were too wide, too open, then that’s what causes us the biggest problems.

“But we have experienced this before and we can take that into the game.”

We will soon find out all we need to know about Qarabag, and in some perverse way it would almost be a let-down if they turned out to be useless, given what everyone who has seen them has said over the past week.

“They play the same formation as us,” said Deila. "They are a very good team with different qualities in different areas. They have good relations, especially on the sides. They have a lot of penetration so we have to be very strong defensively. If we do that then we’ll get the spaces to create.

“They’re quite similar to Legia Warsaw who we played last year. We are meeting a good team.”