RONNY DEILA did not come to the Celtic hot seat blind.

As soon as the Parkhead power-brokers contact the Norwegian, the ex-schoolteacher got stuck into his homework.

He accessed every resource and reference available, from DVDs of the previous season's games, to reports on key matches and figures.

Deila also used his network of contacts - including Stefan Johansen, who he had sold to the Hoops from Stromsgodset for £2million in January - to get the inside track on the players he was inheriting from Neil Lennon.

After four years under the former skipper's charge, a pecking order of first-team players had been clearly established.

Gaining information about the likes of Scott Brown, Charlie Mulgrew, Fraser Forster, Emilio Izaguirre, Kris Commons, et al, was easy.

But what Deila has had to wait to find out is what lies beneath.

The top tier of players are almost all internationals, well-established and well-known.

The group which Lennon liked to refer to excitedly as 'bubbling nicely below' could be more important than ever if, as expected, Deila sticks by his tried and trusted strategy at Stromsgodset and opts to promote from within rather than plunder the transfer market for players he hopes can improve his side.

While many Hoops fans will continue to call for the club to re-invest at least some of the £50m earned in the past couple of seasons through qualification for the Group Stage of the Champions League and from player sales, the prospect of seeing the club return to its roots by developing its own talent excites many others.

Of course, whichever route Deila elects to take in terms of adding to his first team - and it is most likely going to be a combination of both - the bottom line is that the team must keep winning.

Nowhere is this more important than in the key Champions League qualifiers and play-off games which will mark the beginning of Deila's competitive reign as manager, and the defining moments of the club's entire season.

Bomb at this stage, and the manager could well find that delving into the transfer market in any serious sense might be an option denied him.

So while Deila is more than pleased at what he is seeing as his young players produce during their pre-season warm-up games in Austria, they might be required to take a back seat when the qualifiers begin in Reykjavik next week.

Against an Icelandic side which is well into its season, this looks like a job for those who have been over the early-season course before.

Should Celtic get a positive result in Reykjavik, the second leg would provide the chance for a mix of youth and experience.

The fact that this tie will be played at Murrayfield has already placed it firmly in the unusual category, and youthful exuberance could be a useful antidote to any nervousness about strange surroundings.

However, that is too far ahead for Deila to allow his mind to wander.

He has one final warm-up game to go - against Dukla Prague tomorrow night - before he must decide on his line-up for Tuesday's game against KR Reykjavik.

Already denied the services of skipper Scott Brown, the team sent out to start against Dukla should give some serious hints towards who the fans can expect to see in action in Iceland.

The kids took over from the first-team regulars for Tuesday's win over LASK Linz, allowing their seniors - who started the previous two games - to get some much-needed rest before one last push tomorrow.

Several of the Under-19s and 20s graduates have taken the opportunity to impress.

Deila is giving them every encouragement to keep it going as he has made it clear he does not operate a no-entry policy to those trying to step up to the first team, no matter how lacking in game time they may be.

There is no them-and-us as seasoned pros and callow youths train and play bounce games together.

That makes it easier for the two groups to mesh seamlessly in the pre-season matches.

And Deila wants to see more of the same as they go forward together as one group into the new season.

In particular, he likes the enthusiasm and energy the kids bring to proceedings, two vital ingredients in the recipe for success he is trying to concoct.

The older heads came in for criticism from the boss for what he considered a lack- lustre performance against Rapid Vienna last Sunday.

They had front row seats to see what the manager wanted when the kids, and a smattering of fringe men plus others returning from injury - including Nir Biton - took to the field in Linz.

Deila reflected: "I got the changes I wanted from the Rapid game, especially the attitude.

"It was up, and you can see what we can get when all the players are ready to play matches.

"Over time, we want to control games and have a very quick team with good intensity, and this was a good start.

"But there is a lot for us to work on."

Deila spends as much time working on the mental approach as the physical development of his players.

That applies to young as well as old, though it can be the case that those stuck in their ways find it tougher to adjust to what is now being asked than those fresh to the game who, at this fledgling stage of their careers, are more malleable.

Deila demands a positive reaction from everyone, and has already made it clear it is his way or the highway at Celtic under his management.

The message is getting through, and, speaking to the club's official website, he said of Tuesday's performance: "I was very happy with the attitude of the boys. It was 100% from the start.

"There was tempo in the game, and there were a lot of good performances as well.

"They were more confident and comfortable on the ball, so people started relaxing more. That's very positive.

"The performance was what I wanted.

"I'm happy for that and we will move on from this."