Former Manchester United manager Sir Alex Ferguson has told ESPN FC that he expects Spain's dominance in Europe to end in the near future as Cristiano Ronaldo and Lionel Messi are getting older.

Spanish clubs have won the Champions League (Real Madrid twice, Barcelona once) and Europa League (Sevilla three times) for the past three years, and have three teams in the quarterfinals of the Champions League again this season.

However Ferguson, who won the Champions League twice during his 27 years in charge of Manchester United before his retirement in 2013, believes that another country may soon take over at the top.

"I think success is cyclical," he told Sebastian Salazar in the Heineken ESPN FC Boot Room. "If you think about the 90s, it was AC Milan. In the 70s, Ajax and Bayern Munich. In the 80s; Liverpool. In the 90s; Italy, AC Milan. Then England had a great spell with three teams about six years ago all in the semifinal. We [Man United] were in three finals in four years.

"[Now] the domain is in Spain. There's no question about that. The same question could be asked about why are the German teams, why are Bayern Munich not winning the Champions League? Why are the Italians not winning it? Why are the French not winning it? And why are the English not winning it?

"I think the moment, the cycle is with the Spanish teams. They're the best, and that's why they're winning it. But that will change, that can change. You know, [Cristiano] Ronaldo will get older, [Lionel] Messi will get older. Can they replace these players? And I think the cycle will change."

One thing that has changed massively since Ferguson's early years at United is the amount of time managers are given in charge of their clubs. With Arsene Wenger currently the longest-serving in England, yet under serious pressure at Arsenal, Ferguson believes many young managers are expected to do too much too soon.

"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," he said.

"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.

"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."

Ferguson also revealed one of the secrets to his success that brought him 13 Premier League titles, five FA Cups, two Champions League trophies and the acclaim of being the most successful manager in British history.

"Losing is the worst," he added. "You lose a game, you have to do something about it. I responded really well to losing and the next morning I had a purpose about me.

"If you look at, for instance, we were second six times in the league in my time. The following year we won the league. And that was done because I had a purpose to make sure it didn't happen again."