Sir Alex Ferguson claims opposition to Kieran Richardson from Manchester United fans forced him to sell him to Sunderland.
The United chief says it was better for the player to move on after he came in for stick from some sections of the Old Trafford faithful.
He let Richardson move to the Stadium of Light in a £5.5million switch in the summer, so linking up with former United team-mate Roy Keane at the Stadium of Light.
Ferguson told the Sunday Express: "I let him go mainly because some fans were getting on his back and I don't like that.
"Kieran has great ability but he isn't going to flourish if he hasn't got everyone behind him.
"So when Sunderland made a good offer, I decided to accept and send him on his way with our best wishes."
While landing Richardson, the Sunderland boss missed out on striker David Nugent and defender Leighton Baines in the summer transfer market.
But a reflective Keane said: "I don't think the Nugent one was ever going to happen and I don't think Baines was ever going to happen.
"If the lad is an Everton fan and he wanted to go there, then good luck to him.
"I'm not sure that people from Liverpool are too keen to sign for an ex-Man United player."