STUART ARMSTRONG is a contender for Celtic's player of the season. Given the competition faced by the midfielder for that accolade, it's no small compliment.

It is fair to say that under Ronny Deila, the man who brought Armstrong to Celtic Park in the first place back in February 2015, he did not look half the player he is today. Often shunted out wide, the young hopeful who was the shining light in fledgling Dundee United team didn't even look like showing a glimmer in a Celtic line-up he struggled to hold a place in.

His transformation from a bit-part squad player to being one of the key cogs in this rampant Parkhead juggernaut was illustrated perfectly during Sunday's Old Firm draw with Rangers. Of course Armstrong was the man to get the goal to put Celtic 1-0 up, drilling a low shot beyond Wes Foderingham from the edge of the area.

Read more: Maurice Johnston on Pedro Caixinho, a strong Rangers and Moussa Dembele being worth £30m

It was his 11th of this special campaign. Yet, it was the way in which Celtic's thrust and tenacity crumbled as he left the field of play after 73 minutes. It is no surprise that it was at this stage in proceedings Rangers' resurgence grew to provide Clint Hill the platform in which to level the game in the dying seconds.

That sort of influence is down to two factors. One, the hard work and endeavour of the studious 24-year-old to haul his career in an upward trajectory, and two for Brendan Rodgers to help point him skywards in the first place, as Armstrong knows only too well.

“Since he [Rodgers] came in, we had the initial conversation at the start of the season and how he wanted me to go about my business at Celtic,” said the Scot about the Celtic manager. “That really spurred me on and gave me a great platform and opportunity to work my way into the side and play in my favoured position. I owe him a lot for reigniting my career at Celtic.

“I had been named in the Scotland squad a couple of times, first at Dundee United and then at the start of my first full season at Celtic, but I got an injury so that was a bit of a disappointing time. It was very tough to take as I have never been capped before and it was a great honour to be called up, so to decline with an injury was very disappointing.

“It was a bit up and down after that but since the gaffer has come in he has revitalised my career. He moved me into the middle and I have built on that in training, working very hard in training and contributing in games with goals and assists. It’s been a good season of progress so it’s been very nice to be rewarded with a Scotland call-up.”

Read more: Maurice Johnston on Pedro Caixinho, a strong Rangers and Moussa Dembele being worth £30m

Armstrong's rejuvenation has not gone unnoticed, particularly by Gordon Strachan. The Scotland manager sat at the back of the Celtic Park main stand on Sunday watching the Inverness-born midfielder drive the Ladbrokes Premiership leaders forward, much like he has done for most of the campaign.

It came as little surprise to anyone watching the game, or indeed any Celtic fan who has grown to appreciate Armstrong over the last few months, that he was named in Strachan's squad to face Canada and Slovenia in the upcoming international break. It actually makes you wonder how he hasn't received a cap already.

Barring injury, it would be nothing short of a travesty if he is not named in the starting line-up for that World Cup qualifier against Slovenia at Hampden on March 26. Given the Scotland manager appears to have filled a large chunk of this squad on form players rather than the old favourites, one would hope that most certainly will be the case.

Still, the man himself is content to simply look forward to seeing a few familiar faces, savouring the big occasion - as he has done for Celtic so much already this season - and leave the football to take care of itself.

“I’m very happy,” Armstrong told the Celtic View. "It’s a proud moment for me and my family. My brother and my dad and my step-mum all got in touch which was good, saying they were delighted for me and proud.

“The Celtic boys in the squad sent messages of congratulations and a few other boys, including Andy Robertson, who I played with at Dundee United, texted me as well. It will be great to catch up with him as I haven’t seen him for some time, along with some other old faces in squad. I'm really pleased about it and very excited about meeting up with the rest of the squad.”