"It seems that I'm the bad guy in the film, but it's not like that," said Koeman.
"From the first day, since the call, I've shown respect for the player and the person that he is. He has trained to the max while he's been here. I always told him that he would find it tough to play but if he stayed he would be one of the squad."
He added: "It's a club decision. Before signing my contract the club had decided to change things and I backed this decision. It's not just a decision of mine as the coach, but they have tried to change the team and now there are a lot of young people here. Luis and I respect each other and spoke openly about the future. Now he's got the chance to go to a club like Atletico, I wish him all the luck in the world."