STEFAN Johansen is beginning to blossom - and Celtic boss Ronny Deila believes he is finally putting down roots at Parkhead.

Goals from the Norwegian midfielder in the two Europa League ties against Astra Giurgiu and in the crunch SPFL win over Aberdeen before the break for international matches confirmed how important the 23-year-old has become to the Hoops.

His move to a more advanced position allows him to get on the end of chances which, previously, he had been trying to create for others.

However, Deila - who knows all about the range of qualities Johansen has to offer, having signed him for Stromsgodset then developed him into a player for whom Celtic were prepared to pay £2million back in January - wants to tease even better performances from the rising star.

The Parkhead boss has watched Johansen carry his club form into international matches for their country, and is confident that, when the Hoops get back into action against Dundee on Saturday, his countryman will pick up where he left off at Pittodrie.

Deila said: "Stefan has been unbelievable in the last month.He is stronger and is running more and faster - and he scores goals now."

Due to his past association with Deila, Johansen has been an easy convert to the diet, lifestyle and tactical changes Neil Lennon's successor has been steadfastly introducing to the Celtic squad since his arrival in July.

The fruits of this are beginning to be recognised by all as Celtic stand on the cusp of qualification for the last 32 of the Europa League, prepare to face Rangers in the League Cup semi-final and stand proudly at the top of the SPFL for the first time this season.

With a tough Scottish Cup tie against Hearts at Tynecastle also on the horizon, it is vital the team does not lose any momentum in this international break.

For men like Johansen, the games - either for his country or his club - can't come quickly enough.

He could do nothing to prevent Estonia defeating Norway in a friendly last mid-week, when former Stromsgodset team-mate, 15-year-old Martin Odergaard, came on for the last half hour.

But last night, Johansen helped his country secure another three vitals points in the race for France 2016 with an assist in Nordveit's 25th-minute goal in their 1-0 victory in Baku against Group H strugglers, Azerbaijan.

Deila watched both games closely and sees a man hitting the top of his game, and insists it is not just Johansen's impressive strike rate in recent weeks which has been worth noting.

"I see the creative side of him also, which I saw when he was at Stromsgodset," said the Hoops boss.

"Stefan has been here now for 10 months, and has started to settle in. He is a leader, and that is what we need."

What Celtic have also needed was the kind of series of positive results which they put together in the seven-game mini-series between the recent international breaks.

Six wins and a draw across three different competitions has not only allowed Celtic to make significant progress towards the domestic Treble Deila has set as their target, but also silence many of the critics who doubted if the former schoolteacher had what it takes to continue the success of Lennon, who had led the club to the last 16 of the Champions League and to a hat-trick of championships.

Normally, when such a big job becomes vacant, it is because the previous incumbent has failed. In this case, that could hardly have been further from the truth.

Deila knew from the outset he had big boots to fill, which is one reason the changes he implemented when he arrived were put under so much scrutiny, many clinging to the adage: If it ain't broke, don't fix it.

Asked if he considers everyone now believes in him and his methods, Deila answered: "I hope so.

"When you take over champions, it is always hard. They have been successful, and new people are coming in. We need to get more and more togetherness and agree on things.

"Winning at Aberdeen last week was a fantastic achievement, and I feel more and more together with the players."

Meanwhile, Deila is awaiting news of the hamstring injury which forced Mikael Lustig off at half-time when Sweden drew 1-1 with Montenegro.

The defender immediately headed back to Glasgow and said: "It was not cramp. I tried to stretch, but knew immediately that it was something.

I'll go home and see what it is about. Hopefully, it's just a small rupture."