It is 9.15am on Thursday at St John’s Church of England primary school in Fulham, West London, and the lady at the security gate says to follow the blue footprints to find Alan Shearer. The former Newcastle and England centre-forward is doing a corporate shift for FA sponsor E.ON, and the footprints lead to a large office on the first floor. Ten minutes later the tracksuited Shearer shows up, flanked on either side by representatives from his management company, WMG.

The previous day a friend sent him a text message telling him that Kevin Keegan was Newcastle’s new manager. He was surprised and excited. That evening, Shearer talked about the appointment and his position on BBC’s Match Of The Day. His position is interesting because he was a contender for the job and would have accepted had it been offered.

On Friday, Keegan indicated that he wanted Shearer involved in some role and intended to speak to him to see what could be worked out. They may agree a role, but much depends on Shearer. When he played, nobody ever offered him the vice-captaincy of a team, and that’s the best he can now do. Keegan will need a coach, and though Shearer has his coaching badges, his lack of experience would surely mean he couldn’t start coaching with a Premier League club.

What else? Right-hand man to Keegan? The guy who deals with and helps to keep the players motivated? But that is where Keegan has made his mark. Shearer will also be aware that Keegan once brought Peter Beardsley into the England management set-up, largely because he liked and rated his former player. But there wasn’t a role for Beardsley, and that soon became obvious to and uncomfortable for the former player.

Shearer will be more circumspect because his Geordie blood courses with suspicion. As he sits in this Fulham classroom to consider a new round of questions, one of the WMG flunkies sits alongside, as if Shearer has suddenly developed the need for a minder. Hell shall freeze before Shearer looks for a minder.

He was walking off the golf course in Barbados when a friend called to tell him of Sam Allardyce’s sacking. It wasn’t something he had expected; he believed that Allardyce needed more time and thought he would get it. Despite a reputation for blandness, Shearer’s hardness is what informs his opinions. “Sam might have deserved more time, but when you pay £280m for a club, you can do what you want with it. And Sam wasn’t Mike Ashley’s appointment, and that went against him.”

Seven or eight hours after the announcement on Allardyce, Shearer received a phone call from the Newcastle chairman, Chris Mort, who told him the club would be appointing an experienced manager in his place. “So I wasn’t really a possibility for the job,” says Shearer. “I told him if I could help in any way, I would. I understood their decision and respected it.”

When Shearer played and Keegan managed, the centre-forward liked a card game, and his understanding of the odds meant he kept an eye on the betting to succeed Allardyce. Keegan’s name, he noticed, never went out in the betting, and though Shearer hadn’t imagined that Keegan would want to return, he was not shocked. The fans, he says, know what they will get with Keegan; great passion, great commitment, entertaining football, which is precisely what they want.

You suggest that a manager who has always been fired by enthusiasm seemed to have less and less of it for every job he took after leaving Newcastle in 1997. “Possibly so, but he’s had a break, three years, he hasn’t watched a lot of football and he will come back refreshed. There will be a lot of enthusiasm because that’s what he’s about. There will be honesty too, and it will be one hell of a rollercoaster ride.”

But how can Keegan recruit well when he hasn’t watched football for three years? Recruitment, say the brighter chairmen, is what determines the success of the manager. Before being offered a job by Keegan, Shearer is ready to defend his man. “In management, a lot of it comes down to man-management and buying and selling players,” he says. “If it comes down to man-management, which I think it does, Kevin is very good at that.

He goes into a dressing room and he lights the place up. I’ve been there.”

You suggest to Shearer that what Newcastle need is Mark Hughes’s pragmatism and team-building ability. “You should ask what the Newcastle fans want,” he counters. “Entertaining football, that’s what. They are prepared to accept an occasional 4-3 defeat if they are being entertained, because they work really hard all week to pay to watch their team.” We talk about his possible role at the club. People suggest that he won’t like being a No 2. “Are you telling me that or are you asking me that?” he says. “I don’t know that I can be a No 2, or if I can be a No 1. I haven’t said I would like to work with Kevin because I don’t know if he wants a No 2 and I don’t know if I would want to be a No 2, but I would be a fool not to speak if he rang me up.”

Even though the two men haven’t spoken for a year, the phone conversation is likely to be agreeable. Sir Bobby Robson has spoken of Shearer being “the ghost at the shoulder” of whoever manages Newcastle United. “I can understand that to a certain degree,” he says. “But if you go to the men who’ve been there since I retired, Glenn Roeder and Sam Allardyce, they’ll tell you. I’ve been to the training ground once in that time. I go to a match once a month, if I’m lucky. Even then, I go to the ground, into the car park, a lift to my box, I watch the game and am away immediately after the game.

“For anyone to suggest that I know exactly what is going on at the club is totally wrong. You ask Sam Allardyce how many times he’s seen me either at the ground or the training ground, and I can guarantee you the answer is none.

“But I am the club’s all-time leading scorer, I love the area, I love the club, I was born there, I have my home there. I can’t do anything about that.”

Keegan can, and it is likely that he will.

Alan Shearer was visiting St John’s Church of England school to promote E.ON National FA Cup Schools Day on April 24. Go to www.eon-uk.com/ nationalfacupschoolsday for further information