Pep Guardiola admits winning the treble with Man City has made it harder to keep some of the more experienced players at the club.
City secured the Premier League, Champions League and FA Cup in a historic last campaign but have since lost both Ilkay Gundogan and Riyad Mahrez to Barcelona and Al-Ahli respectively.
Kyle Walker has also been heavily linked with a move to Bayern Munich while there continues to be uncertainty around the future of Bernardo Silva.
And Guardiola believes the difficulty of surpassing the achievement of winning the treble may be a factor in players deciding whether or not to leave the club.
“When you’ve won the treble, it looks like the job is done,” he said.
“And the players, most of the players of 32, 33 years-old like Ilkay and Riyad said ‘we arrive here to win the Premier Leagues and after all the people are asking about the Champions League and it will not be complete unless we win the Champions League’.
“Some players feel, okay, I want a new experience. I will not be the guy to say no, no, no for a contract.
“But at the same time we have to take an agreement with an important part of the club, and the club is not me. The club is the business.
“Of course, in this case me and Bernardo and Kyle talk many, many times in the last month and even years about how important they are for us.
“What’s going to happen, I don’t know, but it’s not going to happen if both clubs don’t arrive (at an agreement) because they are both massive, important players.
“When we lose these type of players, we have to go to the market to buy a replacement. And these type of players don’t cost 10, 20, 30, 40, 50 million, no. It’s more expensive than that.
“We need that money as a club to reinvest in players, to make the team as strong as possible to defend the crowds that we won, to play good and to win a lot of games for our people.”
City have signed just one player so far this summer in midfielder Mateo Kovacic from Chelsea, but Guardiola also confirmed RB Leipzig defender Josko Gvardiol is undergoing medial tests with the club ahead of a £77m move.
Barcelona are among the clubs keen on a move for midfielder Bernardo Silva and while Guardiola did not rule out further departures should players want to go, he says it will depend on the offers City receive.
“I said from day one until the end, I don’t want any player who doesn’t want to be here,” he said.
“I want to work with the guys who want to stay, who want to work with my decisions and the backroom staff and the players.
“But after we have to get an offer. We didn’t get an offer, a proper offer so that’s why. What can I say? He’s our player (Bernardo Silva), if they want him they will take a plane, they will come here, they will talk with our sporting director to arrive at an agreement.
“When we go everywhere to buy a player as Man City, it’s 10 or 15 million pounds more expensive than other clubs. All the time it is like that.
“If they want really, really important players, first they have to make an offer and it didn’t happen. And if it doesn’t happen they are going to stay and we are going to fight to extend the contract to be with us. It’s as simple as that.”