Manchester City boss Sven Goran Eriksson says it was a difficult decision to transfer-list Danny Mills yesterday.
He told City's website: "It's never easy.
"I have known Danny Mills a long, long time. He played a whole World Cup for England in Japan and did very well.
"Danny Mills is a super professional football player and is probably one of the fittest we have here. But sometimes maybe it's time to move on and I'm sorry about that.
"He is a nice man, a good lad to have around and gives everything out there, you always know what you get from Danny and that's 100%. He doesn't have any other gear other than 100%."