Yaya Toure, who signed a one-year contract at the end of last season, joined City from Barcelona in 2010.
And as he prepared his side to face Huddersfield on Sunday and Brighton on Wednesday in two home games, Guardiola confirmed that the Ivory Coast international will be leaving the Etihad Stadium.
“The Brighton game, we will focus on winning and Yaya. We are going to try to win the game for him,” he said.
“Yaya came here at the start of the journey. Where we are now is because of what he has done. He was a key player.”
Guardiola also confirmed he will be at the Etihad next season but will not be drawn on the possibility of a new contract.
“I stay for sure one more year. We have three more games. We have time for everything in life,” he added.
“What we have to think about is winning another game. We can break huge records but the target is to win the game.
“Of course it will be a special day. We are going to enjoy it.”