WHEN Ronny Deila wishes Malky Mackay good luck he does so with the unspoken implication that the SFA performance director will need it. Arriving in Scotland with glowing credentials for developing young players - he had the prodigious Martin Odegaard in his Stromsgodset first team at the age of 15 - the Norwegian is utterly damning when he discusses the culture that he encountered in Scotland for bringing through native talent. And this was a man with the best academy in the country at his disposal.

It was not long into his two-year reign at Celtic that the Norwegian began eulogising about the talents of a left-sided player called Kieran Tierney. Other young players in the academy also got a taste for first team football under his watch, players like Callum McGregor, Eoghan O'Connell and Liam Henderson, even though it was judged best for the latter's development to test him on loan spells at first Rosenborg and then Hibs. Not long after celebrating his 16th birthday, Jack Aitchison was celebrating a debut goal in a 7-0 rout against Motherwell.

But, quite simply, he expected better all round. "It is not good enough," Deila told the Sunday Herald. "I feel the development of young players in Scotland is way behind the European level. And a long way behind Scandinavia. It is about the way people train, the games, the pitches, being professional with your work, methodology with your players. The culture has a long way to go. Good luck, that is all I would say to Malky Mackay."

While Mackay is tasked with implementing the SFA's new brainchild, titled Project Brave, which envisages a drastic cut in the number of players gaining access to academy football, the Norwegian knows that all that development work comes to nothing if you don't have head coaches at the top level prepared, or incentivised, to play them in their first teams. "The most important developer is the head coach," said Deila. "The academy at Celtic doesn't have a chance if the manager isn't interested in what they are doing. But we had Eoghan O'Connell, Callum McGregor, Kieran Tierney, Liam Henderson in two years so it wasn't so bad."

Now back managing at Valerenga in his homeland, Deila's comments come in a week when Gordon Strachan can name a side with an average age of 29 for an international friendly against Canada. But they should not be interpreted as a criticism of his successor Brendan Rodgers, who he feels has similar thoughts about the game and is equally invested when it comes to taking a hands-on approach to the youth team.

If there is a problem at Celtic, it is a system problem. Aitchison, still just 17, thus far has had to settle for just one substitute appearance under Rodgers, as has Anthony Ralston and Jamie McCart, while Calvin Miller has made one start. While winning the league by springtime could provide the Northern Irishman with greater opportunities to drip feed his young players into action, even then the imperative to win every match you play in at a club like Celtic doesn't go away. There is an unbeaten run to preserve and a Scottish Cup semi-final on the horizon.

"You get a different opinion from everybody you ask," said Deila. "But I know I improved the culture at the club. I tried to be around the youth department a lot. I tried to change the culture and the players started understanding what I was looking for. I wanted them to reflect, to always go out onto the pitch at 100% and devote themselves to a 24/7 life as a footballer. Diet was just one of the things, it is about making sure you are at 100% every day, injury prevention, things like that. I know I did a lot of positive things that way."

It is a little-known fact that Deila is responsible for Scotland's log jam at left back. Kieran Tierney, who is vying with Andy Robertson and Lee Wallace for inclusion for Scotland against Slovakia tonight, actually played most his youth football as a left winger until the Norwegian intervened. Now, with with more than 60 first team appearances under his belt by the age of 19, and Barclays Premier League sides such as Arsenal, Manchester United and perhaps even Sunderland credited with an interest, it appears likely that the player will be the next big name departure from Celtic Park. Deila knew he had a phenomenon on his hands when he would bring the Isle of Man born player into first-team training and everyone was afraid to play up against him.

"I saw very early that KT had something special," said Deila. "They played him a lot on the wing and I kept telling the manager of the Under-20s that he has to play left full back. He can go forward and he can defend so he is a full back. So they started to play him there but in the beginning he had a lot of problems with cramps and things like that. We had to build him up but he attitude he showed was unbelievable. I don't care how old you are, you have to show in training each day that you are better than the other ones. He would come into training and no-one would want to play against him.

"He is going to have a fantastic career," the Norwegian added. "His time will come - he will go to a bigger club. Technically I still think he has to improve a bit on his passing and first touch. If he can do that, then he can go as high as he wants. But he already has that experience and maybe one more year. His chances will come."

The Scotland team which Strachan names today is likely to feature no shortage of Ronny Deila's favourites. Tierney will play - assuming he wins his arm wrestle with Robertson - as will Craig Gordon in goal and Stuart Armstrong, who the Norwegian signed along with Gary Mackay Steven from Dundee United for a combined £2m fee. But no-one elicits more pride in the former Celtic manager when he considers their performances this season than Scott Brown, who has become so important for his country that they are prepared to keep him going on a game-to-game basis.

Having been player of the year in his first season, Brown underwent a knee ligament operation during his second campaign, then soldiered on for months with a bad hamstring as the Norwegian's time at the club petered out. While this self sacrifice was often to his detriment - such as being off the pace in last year's Old Firm Scottish Cup semi-final defeat - the Celtic captain never had a bad word to say about the Norwegian, a man who stuck by him after he was pictured sitting on an Edinburgh pavement eating a pizza after a night out. The respect is clearly mutual.

"I had a very good relationship with Scott," said Deila. "He was a very good leader on the pitch and off it - he helped with getting a good environment and a good mood in the group. He got a good break this summer, and that allowed him to come back fresh. He has been playing great all season. I saw him against Rangers when they won 2-1 away and he was fantastic.

"He maybe played a bit more sideways when I came in at first and it was maybe a little bit boring to watch him but now he is so good at playing forward passes," he added. "He can open up the play a lot more so I think he has developed a lot. He needs to stay fit and injury free but of course he can keep going for a few more years. You should see the way he trains - he tries to give the impression he is light hearted and having fun all the time but he is so professional. As I said to the players, every day must be an FA Cup final. When you have a captain like that it makes it easier."

Deila's development work for the Celtic cause might not be done just yet. Having brought players to the club like his countryman Kristoffer Ajer, who is now playing on-loan as a centre back at Kilmarnock, perhaps a loan arrangement to Valerenga could make sense for some of the youngsters on the fringes of things at Parkhead. "I hope in the future we could find a loan that is right for Celtic and the player and for us," he said. "We just haven't had the right player yet."