RONNY Deila spoke last night of his delight at Stuart Armstrong's elevation to the Scotland fold and said he deserves credit not criticism for his role in the player's development. Those who feel the midfielder, set to get the nod from Gordon Strachan in his preferred advanced central midfield role in tonight's World Cup qualifier against Slovenia tonight, was going nowhere until Brendan Rodgers replaced the Norwegian at the Parkhead club tend to forget that he might still have been at Dundee United had Deila not given his blessing to a £2m joint move for him and Gary Mackay Steven on deadline day in January 2015. While Deila often played him wide left of a front three, a position where he was unable to prove his true worth, the Norwegian feels he nonetheless gave him valuable experience of the demands of Celtic at a time when he wasn't ready to dominate games the way he does now. He has scored 12 goals in 37 matches already this season and contributed plenty more besides.

"Stuart Armstrong couldn't come straight into Celtic and be the best player at Celtic when he had just left Dundee United," said Deila, now manager of Valerenga in his homeland. "He needed time. Now, once he has one and a half, two years, under his belt, he is starting to adapt to playing at Celtic.

"He played central for us as well at times too," added Deila. "But we had Tom Rogic and Stefan Johansen there, Stefan wasn't a natural No 10 but he did well the first year, and pressed the game well for us. Tom Rogic did well too and we did play Stuart in the central as well sometimes. I agree that he has made this [central midfield] his best position. But at that time I think he needed more experience to be able to play there.

"I am so happy that he has made it, and developed that way. He was a player that we believed in. We bought him for some money and everybody needs time to adapt. That is the issue when you have clubs like Celtic. You don't have the time. Because you have to win AND develop."