Keane, who attended the three-nil loss to Manchester City at Old Trafford on Tuesday night, said: “It’s tough going for United at the moment. It’s not a lack of effort, I’ve seen a few of their games. They’ve lost a bit of confidence. They’re human beings. But it’s not going to get any easier in the next couple of months.

“There’s a bit more pain to come. If they play against Bayern Munich like they have in the last two weeks then they’ll be in massive, massive trouble. At the Liverpool game, I thought United would be okay but they never turned up. Against City, I thought they’d be alright and they never turned up — my God they better turn up next Tuesday night.”

Nevertheless, Keane reckons David Moyes deserves to be given the time required to put things right.

“He’s got vast experience and good staff,” he said. “A couple of senior players, Rio and Giggsy, they’ve got to step up to the plate. One or two of the new players are getting criticism but it’s up to the players who have been there a few years who know what United are about. They also need to get certain players in, certain characters to make sure they battle for every minute of every game.

“I think United will be alright and David Moyes will get plenty of time. The man deserves it. Sometimes a manager has to go but get him to the summer, get a few players in and give him a chance. I don’t think people can comprehend the size of Manchester United.

“Anyone who has got any idea about football will know this was the biggest job — to follow Alex Ferguson. Clever people were saying you want to follow the manager after Alex Ferguson. That’s why David Moyes — give the man time, give him a chance. He’s only been in there two minutes.”

Keane, who was speaking in UCC last night at the launch of a new Cork City patronage scheme, also dismissed Stan Collymore’s call that he and Martin O’Neill – two former Forest men — should replace sacked Nottingham Forest manager Billy Davies at the City Ground, insisting his focus is now firmly on his job as Ireland assistant manager.

“Me and Martin have only been in the door two minutes with the senior team and we’re enjoying it,” he said.

“It’s a big, big challenge ahead and there is so much we have to do. Even the Serbia match, it was a learning curve for us in terms of preparation and boundaries with people, even the media and the FAI. Sometimes with this speculation you’d take it as a compliment. Forest are a top club but my intentions are to continue working with Martin and the senior team and to try and qualify. I don’t tend to get distracted by media stuff.”

However, Keane reiterated he would still hope to return to management in his own right in the future.

“The contract (with Ireland) is obviously a couple of years and I’m delighted to work with Martin, Seamus (McDonagh) and the other staff,” he said. “But I never said for one minute that I wasn’t looking to go and do my own thing. I made massive mistakes, particularly at Ipswich, and I did okay at Sunderland but I’m still learning and I think I’m learning under a top, top manager in Martin and I’m enjoying it. But it’s dangerous to look too far ahead.”

On the subject of his autobiographical work in progress with author Roddy Doyle, Keane quipped: “He’s a good guy for a Chelsea fan.”

Keane said he enjoys Doyle’s company, adding: “He’s clever. I didn’t realise how much I had to say. I think he mentioned that over the course of the few months we’d need maybe 80 or 90 thousand words – I think we got that in the first few hours (laughs). There was nothing wrong with the last book (ghosted by Eamon Dunphy) but I was still a player then and I was under the FA so your hands are tied a little bit and I suffered the consequences — a big fine and a ban.”

* For more information on the Cork City Patronage Scheme, in partnership with UCC, see the club website at www.corkcityfc.ie