Old Firm Countdown: ‘I was obsessed with Rangers,’ says Martin O’Neill. ‘I would drive around, listening to their games, hoping they’d drop points… until my wife told me to get a grip!’

Nearly 20 years after he was last involved in Glasgow’s unique sporting conflict, Martin O’Neill has a confession to make.

“I have to say that in the five years I worked there I was obsessed with Rangers,” he says.

‘If we played on a Sunday, for example, you knew it was vital that Rangers scored away points on Saturday.

‘The number of times I’ve sat in the car on a Saturday after we’d finished training and before we met at the hotel, listening to the last 25 minutes of the game at Ibrox.

‘If it was still equal at that point, I would say: please, wrap it up now, wrap it up now.

‘If you turned it off and turned it back on, you just knew the crowd had scored.

“It was wild. To be honest, I did until my wife said to me, ‘Come on, you can’t influence a game at Ibrox.’ But that’s what it was.”

O’Neill was born in Kilrea in Northern Ireland and grew up as a Celtic supporter. He remembers watching the 1967 European Cup final in Lisbon on a black and white television while at boarding school at St Columb’s College in Derry.

And yet, when it comes to the significance of Old Firm games in the eyes of the supporters, he now openly admits he came to Glasgow with a lot to learn.

“When I first started playing football I really thought that even if we lost the four games against Rangers and won the league, that would please the Celtic fans,” he explains.

‘I was at a meeting in a club in Perth and I was told, ‘No, no, that’s not on the agenda.’

‘I was heavily criticized and never expressed that opinion again.’

His first clash with Rangers is enshrined in Parkhead folklore.

On 27 August 2000, his team went three goals ahead within eleven minutes to win the thrilling match 6-2, sending shockwaves through Scottish football.

For a club already in perpetual crisis before his arrival, this was a pivotal moment.

His attempt to immediately dampen expectations by stating that Rangers were still ‘the benchmark’ was seen by many observers as a public facade, but he maintains to this day that his words were sincere.

“I thought Rangers were the benchmark for the very obvious reason that they were miles behind Celtic,” he says. “They finished 21 points ahead last year and they had really good players.

‘I remember Dick (Advocaat) saying when he signed about five guys from the leagues here: “This is my league team, my European Cup team is somewhere else.”

“I thought, oh, good God. So, that was scary at the time. He did scare me.”

These games are full of emotions and can always change in the blink of an eye. O’Neill won 16 of the 27 derbies he took part in and claims that the feeling he had after those precious victories was unlike anything he had ever experienced in football.

“Walter Smith had been saying this to me for a while, that it was relief,” he continues. “I think, honestly, euphoria and relief come at you at the same time.

‘Glad it’s over because the build-up has been almost the whole week. But when you get a result, you’re absolutely over the moon.’

A generation later, Celtic fans have become accustomed to that exalted position. They have suffered just one defeat in their last 12 meetings, and even then that 3-0 defeat at Ibrox in 2023 came after they had won the title under Ange Postecoglou.

Philippe Clement obviously cannot be held entirely responsible for Rangers’ poor performances in this competition over the past decade, but his run of four games without a win on Sunday is inevitable.

O’Neill, who at one point won seven derbies in a row, believes winning and losing are both difficult habits to break.

“Definitely. Absolutely. And you have to overcome that,” he insists.

‘And what happens is, whether you like it or not, that statistic is generated for you right before the game and in the week before.

“You didn’t do it, you didn’t do it. And you know yourself, you’ve got to change that.”

With home advantage and no Rangers fans on Sunday, Brendan Rodgers’ side will naturally start as favourites. The only unfathomable aspect in the build-up is the possibility that both teams will add to their squads before the transfer window closes. Would O’Neill advocate a baptism of fire?

“It’s very difficult,” he insists. “I had guys like Alan Thompson who got sent off (in a 2-0 defeat at Ibrox in November 2004), although (Peter) Lovenkrands went down very easily.

‘So some guys learned relatively quickly and some didn’t, but overall I think once they got into their first game they realized how important it was.

‘If someone makes their debut on Sunday, I think you have to train those guys 48 hours in advance.’

Rangers could certainly do with a couple of debutants who have struggled to rise to the occasion. Rodgers has been the master of this game in two spells, winning 14 and drawing three from 18 games.

Although there are still three league games left this season, extending that series this weekend would be a bad idea.

“It would be a massive step for Celtic to win on Sunday, even at this early stage,” said O’Neill. “Psychologically, Rangers have a lot to overcome at the moment.

‘What is it? One win in the last 12 or something? As unfortunate as you can be, and you can point to the fact that they didn’t do too badly in the cup final and things like that here, but it’s another defeat.

‘It starts playing with your mind. There’s no doubt about it.

“You have to overcome that. And if they lose on Sunday, you know, it’s not a disaster because it’s so early in the season. But it’s a psychological blow. Brendan’s record in this game is really good.”

Martin O’Neill and Graeme Souness were guests on The Warm-Up, the essential preview show from the William Hill SPFL.