QPR boss Mark Hughes won't block Robert Green from leaving in January.
"In the future if any of my keepers came to me and said they felt their future lay elsewhere then we can have a conversation about that and make a decision that benefited everyone," Hughes said.
Hughes insists that Green fully understands the decision to sign Cesar and claims it was always his intention to bring in another goalkeeper before the transfer window shut.
"It's important that Rob doesn't feel that this was a knee-jerk reaction," Hughes said.
"We managed it and that will obviously have some impact on Rob because there will be competition for him.
"He understands that but he has been a top keeper for a long time and I'm sure he will be ready for that challenge. Whoever is out of the team knows he will have to work hard to get back in the side.
"Rob fully understands the thinking behind what we have done although it might impact him throughout the season."