Pep Guardiola tells Manchester United why Man City have been more successful since Sir Alex Ferguson left

Pep Guardiola says Manchester United's high turnover of players and managers is a major factor behind their struggles in the nine years since Sir Alex Ferguson left the club.

The Manchester City boss is in his seventh season at the Etihad, and has faced four United managers in that time. While United have struggled to define their identity in the year after Ferguson, City have consistently built their own and have asserted their dominance over the rest of the Premier League as a result.

Erik ten Hag, who worked as a coach at Bayern Munich when Guardiola was manager there, is the latest manager to try and change United's fortunes. And Guardiola feels that he can be a success if the hierarchy at Old Trafford give him time to implement his ideas.

"I have a lot of admiration for Erik. We know each other a little bit because we worked a year in Munich," Guardiola said. "We didn't have a close relation. What he's done is incredible work in Holland. Ajax in the last years were an example across Europe and United trust and build a team, give ideas and years with him. Welcome. I cannot say anything else.

"He knows, I know, it depends on results. I'm still here because we won in the past, Erik knows it, all the managers before Erik know it. If you win in big clubs you have time, if you don't you are in trouble. The beginning of the season was difficult with Brighton and Brentford defeats but after they come back with incredible energy in the games and got results. This is the best way because results give you time to build what you want. If United decide on Erik, it is because they believe he is the man."

Asked if Ten Hag has the most difficult job in football, Guardiola said United will only get the benefits from their new manager if they give him the time needed to make the squad his own.

He said: "I don't know. Imagine if you took over Man United who had won three Champions Leagues and three Premier Leagues in a row. It would be tougher maybe because now the average is low because they didn't qualify for the Champions League last season. As much you do well it would be better.

"At the end the hierarchy is important to how you believe how much time you give to the manager. The result is part but the club has to look how they train, how they behave, how they handle the locker room and the media. If the club trusts what he is doing, give time. Football, like many things in life, needs time to be solid, to be something.

"If you change players and managers a lot it's more difficult. If it happens, all the managers at United since David Moyes who replaced Sir Alex and all of them - are they not good managers? No way. I don't know the reason why, I'm not there. If it works, good for them."

Guardiola then moved on to the hierarchy at City, explaining how a single focus on the club's best interests from top to bottom is the main reason for the Blues' success in the time United have struggled.

"The club knows exactly what is the target next step," he explained. "There will be zero problem, I'm 100 per cent convinced. They know the strategy right now, the day after tomorrow, after the World Cup, next season, next season. When the club depends on one person it's a problem, it means the club isn't solid.

"The foundation of the club comes from many areas. All the England guys help us to be the foundation of the team. If the club depends on just Pep, it's because we did not do really well. If the club depends on one player it's not a good team. I never buy a player or sell a player, it's not my money, it's the club. Club is most important word.

"Every decision we make is for the club, for the future. They know the way we want to play with me and without me and the way we want to do it. In football like all sports, tennis, golf, you lose more than you win. Important is think that the way you do will give you trophies and titles. The club knows exactly what we have to do."