Former Manchester City midfielder Dietmar Hamann believes Pep Guardiola's side have already peaked under his tenure.
Guardiola's contract at the Etihad Stadium expires this summer and the Spaniard is yet to commit his future either way.
Having missed out on the Premier League title last season, City have already dropped seven points from their opening five matches this term.
In the Champions League, they have made a positive start with six points from their opening two matches following Tuesday night's 3-0 victory against Marseille.
Having not made it past the quarter-final stage since arriving at the club, Guardiola will be keen to ensure City progress into the final four of this year's competition.
After a slow start to the Premier League season and a disappointing campaign last year, Hamann believes City have already peaked under Guardiola's reign and believes he could be near the end of his 'cycle' with the club.
"Historically, he was at Munich for three years and he improved the team, but the players were happy when he left because he was so demanding,” Hamann told talkSPORT.
“I think a manager like Guardiola can’t be at a club for more than four or five years.
“He’s done that at Man City and if you see the players they bring in, there is no continuity and I don’t see them improving enough with the money they’ve spent.
“I think they’ve peaked under Guardiola, I don’t see them winning the Premier League or the Champions League in the next few years.”
