Grateful Guardiola unsure over long-term future at Manchester City

Pep Guardiola admits he is not sure if he has the stamina to follow Alex Ferguson's example and build a dynasty at Manchester City.

Ferguson took charge of Manchester United for 1,500 games before retiring in 2013, consistently rebuilding his squad during his tenure to keep the club competitive, both at home and abroad.

United's board were rewarded for their early patience, with the Scotsman overcoming a shaky start at Old Trafford to win 38 trophies, including the Premier League title 13 times.

City's development has happened at a much faster pace under Guardiola, who, after heavy investment in the transfer market, could secure a treble in his second season in charge.

"I could not do it in the past, for that to happen you have to stay 10 or 15 years in one club," the Spaniard told the media.

"I think when Sir Alex rebuilt the club it was because he was six or seven years with the same people and after six or seven years and then after do it again.

"We have to stay 10 or 15 years. Of course, I think we could do that when you are always hand in hand with the club.

"That can happen but you have to stay 10 or 15 years. I don't know if I have the energy to do that. It depends on that."

Guardiola's squad overhaul was possible thanks to City's Abu Dhabi-based owners, who retained faith in the former Barcelona and Bayern Munich boss despite a trophyless first campaign.

He admits to having doubts after a difficult baptism to life in English football but is grateful the hierarchy remained supportive throughout the tough times.

"The club is good. This season it is easy to say it is good and going well, everybody is happy. It was the same last season," he added.

"In the bad moments, when we see how the club reacts and how they support you. They were there. We had doubts [as a coaching staff] when we didn't win but no doubts about what we had to do.

"That [support from the board] was so important last season and I will never forget that. Now it is easy to support you but last season they were there and I cannot forget that."