Aguero has recently been strongly linked with a move to Los Blancos, but Marin insists there is an agreement in place with the striker that will keep him from joining Real.
Marin said: “Sergio will decide whenever he wants to leave and Atletico Madrid will accept the offer.
“We have agreed with the player and his agent that Aguero will not got to Real Madrid. Even paying the [buy-out] clause will not mean he will go because the player does not want to leave, and Atletico will not allow it.”