Ferguson, 67 on New Year's Eve, has been given a new lease of life by his young team and regrets saying after winning the Champions League final that he "would not be managing here any more than three years at the very, very most".
Now Sir Alex admits he may carry on longer than Sir Bobby Robson, who was 71 when he was sacked by Newcastle United in 2004. On the eve of today's 150th derby against Manchester City, Ferguson said: "The retirement issue is completely out of my mind now. I don't ever think about it. I am not going to put myself in a situation where I say to myself I am retiring this year or next.
"It's difficult to say whether I will be a manager at 70. People ask why I should pack it in - and it is a good point."