Retirement after 22 years as Manchester United [Images] manager is a scary prospect, Alex Ferguson said.

"Now, I am scared to think about retirement," Ferguson said in an interview published in L'Equipe Magazine on Saturday. "I have been on the train for so long that I am afraid my whole body might collapse when I get off.

"When I was about to be 60, I wondered (if I had to retire). I came close to quitting. But I soon realised, and my family did as well, that it was a mistake," the 67-year-old said.

"I have decided not to ask myself the question any more... I am in the penalty shootout of my career. I know that."

Ferguson, who steered United to European Cup victory in 1999, almost retired in 2002 but changed his mind and went on to win the Champions League [Images] again last year with a side regarded by many as better than the 1999 vintage.