The club's record appearance holder says his veteran boss, who turned 69 last month, has an enduring passion for the game.
In an interview with Sky TV magazine, Giggs said: 'I really do not see him (Ferguson) finishing any time soon, he will go on, at least another five years.'
Passion for the game: Ryan Giggs believes that Alex Ferguson (centre) can continue to manage for years to come
He added: 'His desire gets stronger. After a Champions League game we can get back at 3.30am and then a few hours later he will be the first in at the training ground.
'Earlier in the season we had a virus at the club. He got it himself and was dying during the week, really sick, but come the day of the game, he was there in the dug-out. He just loves the challenge.'
Giggs intends to follow Ferguson and become a manager somewhere. He is currently taking his A coaching badge.
Future manager?: Giggs hopes to go into management once he retires
He added: 'I want to remain in football so I can continue to do something I have done since school. If I have a day off I am bored.
'I hope I can be a good manager, I like helping players and improving them. But the life expectancy of a manager is just 18 months, so you do not get long.'
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