Now an agent whose clients include the current Hearts players Christophe Berra and Gary Glen, Mackay is looking forward as enthusiastically as ever to Sunday, when the first derby of the season will take place at Easter Road. Yesterday, however – when he launched his autobiography at Tynecastle in the company of former team-mates such as Walter Kidd, Sandy Clark and Willie Johnston and player-manager Alex MacDonald – was more about looking back at some of the classic matches in which he took part.

"Probably my favourites are the one in 1985-86 when we won 3-1 at Easter Road – Ian Jardine scored, Sandy Clark scored and wee Robbo (John Robertson] got the other one – and the one in 1991 at Easter Road when I scored at both ends and we won 4-1," Mackay recalled. "It was always better for me going into the lion's den and winning.

"Going down there the pleasure seemed to be increased for the supporters, and those two away wins were huge high points. Scott Crabbe would tell you just how high the 1991 one was, because I think we celebrated for about three days afterwards."

As a player, Mackay was renowned for the passion and commitment he put into the game, but when he took part in a match against Hibs for the first time his heart ruled his head, and his game suffered. "The first derby I played in was in 1983 when Robbo scored two, Jimmy Bone scored the other and we beat them here 3-2.

"The gaffer (Macdonald] took me off after 65 minutes. I was physically exhausted, absolutely drained.

"And then the day before the next derby, the gaffer and (assistant manager] Sandy Jardine took me into the office, gave me a tablet, and said 'Take that son just an hour before you go to your bed and you'll sleep like a baby'. And I did.

"Slept like a baby, played really well the next day. And after the game, Sandy Jardine said 'There you are – that's what half a paracetamol can do'."

Yet, while appreciating that players can sometimes be too up for a game, Mackay also knows from experience that it is just as risky if you have team-mates who are unaware of just how keenly contested the match can be. "When they run out on Sunday I think the guys who have never come across an Edinburgh derby before will realise what it's about. I remember Peter van de Ven came to Hearts, and we told him and told him all week – and he was a great player – just how difficult it was going to be against Hibs.

"And he apologised at the end of the game, because even though he had played in the north-east derby and in derbies abroad, he had never appreciated the intensity and the pace of the game.

"And if there's nobody who appreciates that come two o'clock on Sunday, their team will be found wanting. That's why the likes of Michael Stewart and Christophe Berra are hugely important in educating the ones who are new to it.

"Rangers and Celtic, because of the size of the crowd and what they generate, is a massive, massive football match. But for somebody like Michael, or Derek Riordan or Colin Nish, the size of the Edinburgh derby in their eyes is the equivalent of the Old Firm derby."

Mackay has witnessed a lot of turmoil at Tynecastle both during and after his career, and his book pulls few punches. An activist in the Save Our Hearts campaign to prevent the ground being sold by Chris Robinson, he describes the former chief executive as "the only person I hate". He never exactly saw eye to eye with his former team-mate Craig Levein either, and recounts some of the occasions on which the two have fallen out.

Mackay disagreed with some of Levein's actions when the latter was Hearts manager, and feels a lot happier having an impassioned person such as Csaba Laszlo in charge.

He has a fair amount of respect and admiration for the Hearts owner Vladimir Romanov, but believes that the businessman, having made an astute appointment, should allow the manager a free rein on the playing side.

"I want the manager to have full autonomy," he said. "I think at the moment Csaba Laszlo has that on the football side, and he is somebody we should be putting our faith in."

• Maroon Heart by Gary Mackay, with Mark Donaldson (Fort Publishing, £16.99).

Taken from the Scotsman