Over the past 27 months, on the many occasions that Niall Quinn was asked to summarise what Roy Keane brought to his club, he would respond with two words: “Box office.” He used the phrase again yesterday. “He lifted this place off its knees,” the chairman said of his fellow Irishman. But for all the profile, charisma and startling success, theirs was never a story destined for a Hollywood finale.

It might have lasted a month or endured for a decade, but the conclusion at the Stadium of Light was always going to be a juddering halt. It is often football’s way — managers are rarely afforded sentimental departures — but the sport has nurtured few personalities as unpredictable or unreadable as Keane. The only certainty was that it would end like this, although his text message to explain his decision does little credit to his achievement.

In tandem with Quinn — the willingness of the pair to put aside the differences that exploded so spectacularly before the 2002 World Cup finals remains a source of wonder — Keane persuaded a club bereft of hope and optimism to believe in themselves again. Quinn described the process as “reconnection” and in a region where economic and social hardship is a reality, the effect was enormous.

The Sunderland Keane inherited were weighed down by their history and ashamed of their past; memories of the worst points total collected in the Premier League (a record since claimed by Derby County) were balanced by a stadium and training ground where no pictures of previous heroes hung. Keane changed that, creating a spirit of excellence and awakening something else.

When the going got tough, Keane got going

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BACKGROUND

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• Keane must change before Sunderland unravel

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After relegation in 2005-06, the turnaround in the Coca-Cola Championship was extraordinary, with Keane pulling the team away from the bottom and pushing them towards the title. Maintaining their status last season was another milestone, as was his success in attracting established players to Wearside in the summer. Yet there was little love to balance the pulling, pushing and cajoling.

“He’s turned a region’s mindset,” Quinn said. “He was instrumental in developing a winning mentality and that was tough to do when we were at the foot of the Championship. He’s brought standards to this club that are amazing. I’ve tried for a couple of years to keep as much of that pressure off him as possible, but the Premier League is the Premier League.

“I guess it came to that point where Roy thought he’d come to the end of that journey, so reluctantly I accepted that. It’s not the easiest thing to do, but it was the best thing to do in the circumstances. He’s left a brilliant set of players who are five points from ninth place. Go back to the day he came here and we’d have given him the Crown Jewels if he’d have been able to do that for us.”

As Quinn acknowledged, the speed of the decline has been swift and startling. “Five weeks ago, people were dancing in the streets,” he said, a reference to Sunderland’s 2-1 home victory over Newcastle United in late October. “It’s a funny world is football, and this isn’t an easy day.” Since Monday he had been attempting to find a mechanism that would allow Keane to stay, but compromise was an alien concept.

Relationships at the top of the club were fuelled by creative tension, but it was not that which propelled Keane towards the exit, or the arrival of Ellis Short, the Dallas-based businessman who is Sunderland’s majority shareholder. The delays in extending Keane’s contract, which was due to expire in May, were also not to blame, even if they encouraged a mood of instability. “The two of us spoke about three to five years originally and he signed for three and we said, ‘Let’s see,’ ” Quinn said.

“There were one or two discussions, mostly driven by the media, I have to say. Roy and I were always comfortable that it \ would happen after Christmas or later on. In the summer it looked a formality that it would happen, but football changes. We’ve got to kick on now.”

The story is far more fundamental than conspiracy: Keane “lost” his dressing-room. An unforgiving style, an irregular presence on the training ground and unflinching standards helped to forge a soaring spirit among his players during his first two seasons in charge, but the same methods were less appropriate for a more cosmopolitan squad of spikier characters.

Offered the opportunity to reinvent himself, however subtly, and the support to do so, Keane chose to walk. The magnitude of the 4-1 home defeat by Bolton Wanderers on Saturday was too much to bear. “We gave him a bit of time to himself because everyone hurts after a result like that,” Quinn said. “He was down and we tried to move it along, but we couldn’t quite get there.

“Six defeats in seven games builds up its own pressure and Roy’s tough on himself. He’s got huge standards. Old Trafford is a tough game on Saturday, but after that we’ve got a home game [against West Bromwich Albion] and we’re playing teams down there near us. I’d hoped Roy would judge himself after them. But he got to where he got to.”

Keane, who delivered memorable diatribes against the WAG culture, television pundits, slacking players and Fifa executives, was fond of discussing the “bigger picture” and he stayed true to it. “This isn’t really about Roy Keane or Niall Quinn, it’s about the club, that’s the big thing,” Quinn said. “Roy hasn’t been sacked because we’ve a bad team, he’s resigning because we’ve a good team he feels he can’t bring any further.

“There’s a big difference there. You hear terms like ‘amicable’ in situations like this, but that’s actually the way it is. We’ve had a bad few weeks and Roy feels he can’t go on, but I’d say to fans, ‘Look at what he’s left, look at what he’s achieved.’ We’re charged with building on that and I’ve got the full backing to do it.” For now, however, the box office has closed.