The 18-year-old has become a regular for the Scottish Premiership side.
Kieran Tierney has pinpointed his performance in the Europa League game with Fenerbahce near the start of this season as the moment that he proved that he deserved to be around the Celtic first-team, the Daily Record reports.
The left-back could count his previous appearances for Ronny Deila's men on one hand before he was tasked with trying to keep former Manchester United winger Nani quiet back in October. But like most of the challenges he has faced this season, Tierney was able to rise up to it.
Within a couple of months of that performance, the 18-year-old had become a regular at Parkhead and has arguably now established himself as a key member of the squad.
And the defender - who has also now been handed his first cap for Scotland - suggested that it was the clash against the Turkish side that proved that he had the ability to raise his game.
"You can't let yourself get too nervous. I knew beforehand I was up against players like Van Persie and Nani," he told the Daily Record.
"People told me on social media that Nani had won more Premier League trophies than I had made league appearances. But you can’t think about that stuff.
"I think the manager and the fans thought I'd done okay in that match so it would be okay to play me in the league games. It showed I could handle it."
Since being given a prolonged run in the side, Tierney has shown that he is more than just a prospect who the club have high hopes for and thus, want to give chances to.
His defensive ability has seen him often cope with the best wingers that the Scottish Premiership has to offer, while he has also been a threat going forward.
Only Gary Mackay-Steven and Tom Rogic have contributed more assists than the five that the full-back has managed in the league this term, and he will be hoping to enjoy an even more promising campaign next season.