There is a brilliant film called When We Were Kings.

It is a 1996 American documentary film directed by Leon Gast about the Rumble in the Jungle heavyweight boxing championship match between defending champion George Foreman and underdog challenger Muhammad Ali. It superbly sums up an unforgettable sporting era.

Archie Macpherson himself belongs to an unforgettable sporting era. Alongside Arthur Montford he was one of the doyens of Scottish football through the late 1960s, 1970s, and 1980s. Macpherson worked for the BBC, Montford for STV.

It was a joyous time for Scottish football when Macpherson and Montford were the kings of broadcasting. Celtic, Rangers and Aberdeen all won European trophies while Scotland qualified for five World Cups in a row. By Dickens, it was the best of times indeed.

Yes, Macpherson has seen it all and done it all; a rich tapestry of Scottish football seeps out of every fibre of his being.

Very few people in life can count Celtic's legendary boss Jock Stein, former Aberdeen and Manchester United manager Alex Ferguson and Dundee United great Jim McLean as close friends. Macpherson can.

Macpherson wrote the go-to Stein book. Entitled Jock Stein: The Definitive Biography. It is a must-read for every Celtic fan - and is now also available as an audiobook.

After all, in his own words, Macpherson and Stein "travelled the world together". He became Stein's confidante, colleague, friend and biographer. Stein became Macpherson's co-commentator and roommate on many foreign trips.

Macpherson was present in Lisbon in 1967 and at the World Cup in 1982 when Stein managed Scotland. They did the sponsored events and supporters functions circuit together as their friendship grew.

"I was fortunate that I travelled the world with Jock," Macpherson told The Celtic Way. "We went everywhere together. I remember we embarked on a pointless trip to see New Zealand before Scotland played them in the 1982 World Cup finals in Spain. Ally MacLeod was roundly criticised for not going to see Peru or Iran before the 1978 World Cup finals in Argentina. The BBC actually invited Ally to Peru on an all-expenses paid trip to see them playing the host nation Argentina in Lima and he turned it down because he was on big money at the time.

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"At that stage, World Cup fever had taken over and he wasn't interested in going around the world to South America so the BBC did it on their own. Doing so was a veiled criticism of him and for Ally personally, Argentina 1978 was a disaster. Stein knew this and since he had taken over from Ally he didn't want to give off the impression that he wasn't prepared to go on spying missions to watch Scotland's World Cup finals opponents.

"It was a pointless trip and we learned nothing. New Zealand were playing the Republic of Ireland's B team but Stein did it to ensure that he was watertight when preparing for the big event.

"When you do that (travel the world) it is not as if you are knocking on the door at Parkhead and asking for an interview. You become intimate with people - the way you talk, the way they deal with you, the stories that they can tell about themselves and so on - that's how the definitive Jock Stein book came about.

"I got a call from a journalist friend who was very big on Fleet Street, he worked for The Sun newspaper, and he told me he had been asked to write a book about Jock but he didn't really fancy it.

"He said he wasn't up to it as he didn't know him that well. He said he couldn't be bothered going through the history books and he asked me if I would be interested. I told him that I would be and he put me in touch with the publisher and that was it, off I strode. It was a remarkable experience writing a book about Jock.

"It was an education being around him. He could give you a decent conversation on anything - politics, religion, football - he had what is often referred to as a 'guid Scots heid' on his shoulders. Jock Stein really was something.

"I think coming face to face with the backlash that he endured after he joined Celtic - when even his father couldn't wish him well and his best and closest friend from childhood growing up never spoke to him again - opened his eyes to the kind of society that existed in Scotland for many years. He rode that storm perfectly. I admired that greatly about him.

"He loved his football and Celtic had given him a new start in life. He had gone there from Llanelli in Wales so it was not as if he was coming from Inter Milan."

On the night of Stein and Celtic's greatest triumph - the 1967 European Cup win in Lisbon when former Liverpool boss Bill Shankly famously uttered the words "John, you're immortal" - Macpherson reckoned Celtic had one of their easiest contests in European football ever.

The men in green and white dismantled the great but defensive Inter team, with Stein himself remarking: "We did it by playing football. Pure, beautiful, inventive football."

Macpherson came away with a beautiful line himself during Celtic's barrage of the Italian side's goal when he prophetically said: "Will Celtic ever melt this ice age of defensive Italian football?"

Rather than the final against the side which had won two of the previous three European Cups, Macpherson believes that both FK Vojvodina and Dukla Prague put up greater resistance against Celtic than the Italians ever did.

"When Celtic won the European Cup as an adjunct I saw it as a Jock Stein triumph," he said. "I was simply happy and ecstatic at the triumph of Celtic and Scottish football. That is how we all felt about it.

"Celtic battered Inter Milan 2-1. If you look at the history books it's as if they had trod the balancing act on a trip wire in that game but it was nothing of the kind - they were simply superior.

"Celtic had a ridiculous amount of possession. Inter were a defensive team and all they did was defend and counter-attack on that fateful day in May. Laying that aside, Celtic had numerous chances in the game. I know it was a big event and I know it was the winning of the European Cup and it is the most important cup of all but actually Celtic had an easy game in the final.

"They had more difficult games against FK Vojvodina and Dukla Prague en route to the final. When Billy McNeill scored in the final seconds of the home game against Vojvodina, Jock was beside himself in the dugout.

Celtic Way:

"They had a hard game in the second leg of the semi-final in Czechoslovakia when he turned his own philosophy and the club's playing style upside down by defending their 3-1 lead from the first leg by defending. He realised that Dukla were a good side and my recollection is that he expressed regret at having to do that but satisfaction that it worked and the means justified the end."

Ironically, on the night Stein passed away in September 1985 at Ninian Park in Cardiff, Macpherson was in the city but was not on commentary duty for once as he working for the BBC in London as well as giving a speech at Cardiff Castle. When he learned the news he was heartbroken, left utterly devastated, and the words he delivered that night turned into a tribute to his great football friend.

"I was to do interviews after the game," Macpherson recalls. "Don Revie's [the great Leeds United boss] son heard that I was going to be at the game he invited me to do a speech at Cardiff Castle to a group of businessmen. I left the ground not knowing what had happened and we were on our first course when the dreadful news filtered through. Duncan Revie whispered in my ear 'Jock Stein is dead'. "I couldn't believe it. I stood up and I did a tribute to Jock which was a kind of eulogy really.

"I remember interviewing a Rangers supporter the next day for Breakfast TV and we got the cameras and went down into the streets very early in the morning. This guy was bedecked in tartan and supporters must have been up all night wandering the streets and he said to me simply 'we would rather be out of the World Cup and have big Jock Stein back'.

"That Rangers supporter summed up the feelings of every Scottish football fan in the country so eloquently and succinctly. Jock Stein was respected, adored and revered by everybody in football."

No relationship is ever perfect, though, and it took a while for Macpherson to earn Stein's trust because he worked for the BBC. Stein believed that the major TV institutions were ferociously anti-Celtic and pro-Rangers and because of that Macpherson was always in the line of fire. Some of it was friendly, some certainly were not.

READ MORE: Postecoglou, Stein & Puskas... the Celtic through-line that binds football royalty

Things took a turn for the better when Macpherson cold-called Stein one day at Celtic Park and made him an offer which prompted a thaw in their relationship and mark the beginning of a friendship which was to last for the rest of their days.

"We had our moments," Macpherson said. "I worked for the BBC and Jock was convinced that their coverage was biased towards Rangers and tilted towards Ibrox. It was hard going at times and he would brusquely dismiss me way back in the early days of our relationship.

"He once zoomed past me at Pittodrie one night and pointed the finger and told me to tell the BBC never to send Alastair Alexander to Celtic Park ever again. It was part of the game - until I thought 'this can't go on'.

"One day I cold-called Celtic Park, knocked on the door and asked to speak to him. I went in and he agreed to see me. I told him it had to stop. We spoke for half an hour before I invited him up to the BBC and I told him to do the co-commentary with me on the next international match. His eyes gleamed at that. He did it. From then on our relationship changed.

"We both did the famous night at Anfield in 1977 when Joe Jordan supposedly handled the ball and, in my commentary, I said it was a penalty if ever there was one. That was the end of it all and to be fair after that we went on to travel the world together and I wrote his biography."

Macpherson insists that Stein was the trailblazer for every success that was enjoyed in Scottish football, especially at club level. He was, quite simply, a pioneer and had a profound effect on the likes of Alex Ferguson and Jim McLean.

However, for Macpherson, there can and will only ever be one Jock Stein.

"He had a wonderful influence on the likes of Alex Ferguson and Jim McLean," he said. "He was so ahead of his time. Ferguson modelled himself on Stein. Jock instilled in his Celtic players the idea that the institutions and the establishment were against them. Alex did exactly the same thing as the Aberdeen manager. He firmly implanted in the Aberdeen players' heads that the west of Scotland was against them. Travelling south of Dunblane was viewed as hostile territory.

Celtic Way: Archie Macpherson held Jimmy Johnstone in high esteem as a playerArchie Macpherson held Jimmy Johnstone in high esteem as a player (Image: SNS)

"He hated the west of Scotland press - the Daily Record, the Sunday Mail and the Daily Express - and he detested some of the journalists that worked for those papers. He could get on with them but, by and large, he felt they were against them.

"Every now and again a Celtic manager has had a good run - I'm thinking of the likes of Martin O'Neill, Brendan Rodgers and now Ange Postecoglou - and they are all likened to Stein. But Jock Stein is unique, there is nobody like him.

"If anybody comes up with that argument then simply say this to them: how about a man walking into a club going nowhere, losing his first three home games - one of which is against the club he has just left [Hibernian] - and playing to an average crowd of about 16,000... yet somehow two years later they are the European champions. Beat that.

"The simple answer is that you cannot and will not beat that. Ever. Jock Stein masterminded that. It is an incredible story."

While nobody can hold a candle to Stein in terms of football management, two Scots stand head and shoulders above the rest in the pantheon of great players that Macpherson has had the privilege of witnessing in the flesh on the pitch.

"I saw three Scottish clubs winning European trophies," he says. "I don't want to be pessimistic but it will take a hell of a long time for that to be repeated. I have a sense of privilege at having lived through that era. It is unprecedented. Those three games obviously stick out in my mind.

"But the greatest players I have ever seen? In terms of Scots the two that immediately spring to mind are Celtic winger Jimmy Johnstone and Rangers midfielder Jim Baxter.

"Johnstone was voted the greatest-ever Celtic player and rightly so. They were both just completely natural although they were two different players entirely. They were artists in their own way. You could not lay them against each other or even compare them. In their respective categories and positions, they were both outstanding footballers."

Macpherson, in his own inimitable style, was an artist too. He painted wonderful pictures of the beautiful game with his soothing words and unmistakable voice.

He helped define an era for sport in this country and, when it comes to Scottish football, Archie Macpherson is and always will be a national treasure.