Sir Alex Ferguson has reflected on his time at Manchester United and claimed he never imagined he would go on to enjoy the career he did when he first took charge of Old Trafford.

To spend almost three decades at a club is an incredible achievement, never mind doing so on the back of winning as many trophies as Ferguson did with United.

In an interview with ESPN, he has claimed that the club’s history was all the motivation he needed to do well.

When I came to United in 1986, I never thought for a minute I would last 27-and-a-half years. And that was done simply because I had the energy to do that.

I had great energy, and I sacrificed [a lot] — my kids would grow up with my wife, and the role she played was really important. I didn’t need any motivation. You don’t need motivation at Manchester United. The history of that club is enough. So I enjoyed a fantastic spell.

While Ferguson’s success at Aberdeen was the springboard to joining a big club like United, he acknowledges that former players don’t get the same breaks in management these days.

Today I think a lot of players don’t make their mind up that they want to stay in the game until it’s too late. In other words, they don’t have a rounded preparation like I did. They maybe take their badges at 32, 33 and then they expect to managers two or three years later.

It’s a result industry. It’s a serious result industry. You have to win games. And if you don’t have the proper preparation like I did, and a lot of coaches did, you’re going to suffer.

It’s a very, very difficult industry. And of course the other side, as opposed to when I started, was that you have different owners. They have owners from all over the world, with different ambitions — there’s a lack of patience in that respect. But you really need to be prepared to stay in the game. That’s the most important message I could give them all.