Christie weighed just 64kg when he joined the Parkhead side in 2016, but now nearly three years on, he has made the neccessary improvements to his game in order to muscle his way into Brendan Rodgers side.
The youngster has also had his 'x factor moment' according to Rodgers, where he announced himself as a proper Celtic player; he was the difference for the 'hoops' as they beat Hearts in the Betfred Cup semi-final.
And after the match on Sunday, Christie's manager Brendan Rodgers was full of praise for the player, for finally showing the potential that made former manager Ronny Deila splash out £500,000 for his services some years ago.
In speaking on Christie's progress, Rodger's said: "It was a big step for Ryan at the weekend.When I came in, I had a boy of 64 kilos, who played as a striker against Motherwell, and I felt: "Okay, here's a talent, but is he going to play regularly for me?" I didn't think he was, but he wasn't 17 or 18. He was 20, 21, so what would benefit him when it comes to thinking medium and longer term?"
Rodgers continued: "He would benefit from playing games and feeling the pressure week-in, week-out, because coming from Inverness to Celtic is a big jump. Some players cope straight away when they come in as a 17-year-old. Raheem Sterling's maturation level at that age was an example of a kid who was physically strong. There are some players who mature a bit later."
An 18 month loan spell with Aberdeen turned out to be the making of Christie, who is now making waves in the Celtic side after returning to Parkhead this summer on the back of his impressive loan spell.
29 October 2018
Rodgers spoke of the player's loan move, describing the benefits it has had: "We were lucky to send him to a club where he would be under pressure, but still get regular game time. I had a conversation with Derek (McInnes) and that's what we looked at. Ryan went away and had 18 months playing. He played well and still had to develop and grow, but at least he was feeling pressure."
The Celtic boss concluded: "What he probably needed was a big moment in an important game. He's had those at Aberdeen as well in big games - but Sunday can be a real spark for his confidence. Now you see a boy at 23 who I feel is ready now to really participate. Now it's about him and what he does on the pitch. It was about taking his talent and bringing it to fruition and could he take the opportunity?"
29 October 2018
A second half replacement for regular Olivier Ntcham; Christie proved to be the match winner for Celtic at Murrayfield, as his long range strike and a penalty he earned, gave Celtic a place in November's final against Aberdeen.
Christie has many obstacles to nail down a starting berth with the reigning Scottish Champions; Ntcham, Rogic and McGregor are all ahead of him in the peking order.
However if the youngster continues to push himself to develop, he should be getting in the side more often than not for the remainder of the campaign.