One moment proved the difference between victory and defeat for Celtic at Hampden on Saturday, but throughout the season they have once again proven that mentality is a key ingredient to domestic success.
The Scottish Cup final was a close game between the two teams.
It was a game in which Rangers performed well and achieved everything they had hoped for by thwarting the fluency of their rivals.
But the decisive moment belonged to Celtic: a shot, a rebound and Adam Idah scored.
Having achieved the league and cup double, Brendan Rodgers cannot and will not stop.
“Rangers have improved but history will show that Celtic won.”
Saturday's match reflected my memories of this derby as a young player and young supporter.
Usually neither team dominates for the entire 90 minutes, there are periods when one side dominates and vice versa – that's the Old Firm.
As a player, you always know the other team will have chances and the Rangers players must have had that in mind when Abdallah Sima's goal was disallowed.
Yet Philippe Clement's side prevented Celtic from performing at their best in attacking situations.
That meant there were no clear-cut chances for either team, but history suggests Celtic were victorious again.
We've seen their mentality shine through in pressure situations throughout the league and now this team is set for another great day.
“Ida reduces Kyogo's burden”
Ida had a huge impact on the Celtic team as he helped win the match.
He will likely be compared to Kyogo Furuhashi, who has better movement than anyone else in the country, but Idar has an entirely different profile.
He lets me play longer minutes, if it's a more physical game he brings that.
But what he shares with Kyogo is a sense of goal-scoring, and that was on display again at Hampden.
Celtic relied heavily on Kyogo for large periods this season and last season, but Idah has eased the burden on Kyogo and offered something different.
With his loan deal from Norwich City due to come to an end, it will be interesting to see what moves Celtic make in the summer.
“Rodgers and Celtic can't stand still”
The manager will know what to do with Aida and what else to do this summer.
With Celtic and Rangers you can't stand still, you always know whether your rivals are trying to take the league away from you or you're trying to keep it.
“During my time as Belgium assistant coach I watched Clement build a serious team at Club Brugge and Rangers have a good manager.
This weekend is not a time to celebrate, but Celtic will know they need to step up if they are to make progress in Europe and maintain their domestic dominance.
I'm sure the team I watched on Saturday will be even stronger next season and they have a great manager in charge.
Rodgers did a great job at Leicester, he did a great job when he first came to Celtic and he's done the same at Liverpool.
He's not going to stop, managers at that level don't stop, so it will be interesting to see what happens in the summer.
Former Celtic forward Shaun Maloney spoke to BBC Scotland's Nick McFeet.
