Sky Sports News sources have suggested that the England striker now believes he is being asked to prove himself again, despite nine seasons at Old Trafford.
David Moyes has commented that Rooney is needed for cover for Robin van Persie.
That has allegedly left Rooney "angry and confused" and he is now seeking a way out of the club.
The 27-year-old believes that he is at the peak of his career and therefore does not want to spend time warming the United bench as Van Persie's understudy.
He has been linked with Arsenal and Chelsea in recent weeks.