Former Celtic and Scotland captain Tom Boyd once cleared a stadium when he broke into song. Now, the 52-year-old is singing from the rooftops after witnessing a season in which the Parkhead side toasted an unmitigated double treble and stand on the precipice of breaking their own transfer record with the signing of Odsonne Edouard.

“There is a song called treble treble that I use in my spin class and hopefully I’ll be using it again next year!” joked Boyd. “I smiled every time I put on a Celtic jersey – apart from the Inverness game! Listen, I’m of a happy nature. How can you not smile being a Celtic fan?”

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The next derby at Celtic Park will likely see those dressed in blue squeezed into the restricted view area of the stadium.

In fairness, the bulk of Boyd’s playing career at Celtic was spent in the slipstream of Rangers as the Ibrox side dominated the domestic landscape in a similar ilk to how Brendan Rodgers’ side currently lord it over the rest.

But the tables have turned and Celtic show little sign of easing up judging by the recent activity of offer Tom Rogic and Kristoffer Ajer five-year deals to add to the long-term contract of Kieran Tierney. The Parkhead side are preparing a permanent deal for 20-year-old Edouard, a figure that may be eye-watering to the rest of Scottish football but which indicates the position of strength that Celtic are in.

And such has been both the reputation that the club have developed in a business and football perspective of identifying young talent and then selling on further down the line, that Boyd believes there is no gamble in shelling out that kind of money for the Frenchman.

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“It is not [big money] in the realms of world football,” he said. “In terms of Scottish football, yes it is, but it is not a gamble going from what we have seen given that under the stewardship of Brendan he will only get better. Brendan has improved so many players within the ranks here and we have seen examples of that as players have developed.

“The manager will have seen him every day which gives him an insight into it. We have seen him in games, maybe not as much as we would have liked, but the best place to see him is on the training ground. That isn’t quite a game situation but it is a good reflection watching someone every day.”

Celtic’s business model in recent years has put the club on a solid financial footing, a foundation that has been solidified by the club’s success in qualification for the Champions League group stages over the last two seasons.

“I think at this moment in time there is only one club who could afford that kind of money,” said Boyd. “That comes down to how well structured the club is and has been for a long time. The money is coming in because of the success on the park so we can budget that.

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“I don’t know where it goes after that because the money at other clubs is frightening. But, listen, that is what you have got to do. Ask Brendan and he won’t see it as a gamble because he knows the player and knows his quality.

“At a later date he knows that he will have the potential to sell him on and I think we have done not too bad at that in terms of bringing players in and making them better and then selling them, mostly to the English Premier League. There are a lot of players going onto bigger things and getting more money.”

Boyd was Celtic captain when the Parkhead side stopped Rangers from winning ten-in-a-row in 1998. Now, two decades on with Rodgers’ side galloping towards that figure, he has insisted that Celtic’s current position of lording it over the Ibrox side is something that no-one should take for granted.

“I played in the early 1990s when we struggled along,” he said. “There will be older fans out there too, who remember the club struggling before Jock Stein came. So, this is a great time to be a Celtic supporter and player, with this success on the pitch.

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“I would never take this for granted and no, I never thought at that stage that this could happen. But it’s a testament to how the club is run, how professional they are and how they get the job done. This, under Brendan, has been unsurpassed in terms of the double Treble.”

A bigger challenge will be expected to come from Rangers this term with the arrival of Steven Gerrard. A summer of overhauling the squad will be anticipated but Boyd has insisted that his own feeling is that Neil Lennon’s Hibs gave Celtic the biggest run for their money last season.

Whether the Easter Road side can maintain that in the coming term remains to be seen given the players who are expected to leave Leith, but Boyd is optimistic that there will be a challenge put to Celtic.

“I hope they all do get the money to challenge because it will help Scottish football if we have a stronger league.

“Obviously the financial thing is difficult to challenge Celtic.

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“Celtic will concern themselves with bringing players in, selling them on and they are doing that ever so well. They are the best in Scotland at doing that and hopefully the model continues for many years.” And despite the arrival of Steven Gerrard at Rangers, Boyd believes that Rodgers requires little in the way of additional motivation.

The hallmark of the 45-year-old’s time at the club has been the desire for continual improvement, with Rodgers revealing of late than last summer he was just three days into his holiday before he got the fear of how he could top last season’s Invincibles campaign.

The arrival of Gerrard at Rangers offers a different element of intrigue given the shared history the dup have but Boyd has insisted that Rodgers is interested only in what is going on in the East End of the city.

“Brendan has enough motivation at this football club,” said Boyd. “He has been brought up as a supporter and the demands are there to be successful.

“It’s not only to be successful but to entertain. As much as he will take note of the opposition and who comes in, he is looking at how to improve Celtic rather than worry about anyone else.

“He will welcome what Stevie and the rest will do but probably some of the hardest games last year were with Neil Lennon’s Hibs team. Brendan will be concerned with improving here. He’ll start that process by signing Odsonne [Edouard] and one or two others.

“He will be bothered about making Celtic better.”