Former Manchester United assistant manager Mike Phelan says forward Wayne Rooney may want a fresh challenge away from Old Trafford.
Rooney, 27, reportedly asked to leave the club at the end of last season, the second such request in three years.
Phelan told BBC Radio 5 live: "Wayne is at the greatest club you can be at.
Rooney, who also asked to leave United in October 2010, was linked with a move to Paris St-Germain in April while more recently there has reportedly been interest from Arsenal and Chelsea. "Why would you want to jeopardise that, unless you want a fresh challenge and you feel that challenge isn't being met at Manchester United."
He is set to meet with new United manager David Moyes this week to discuss his future.
Arsenal midfielder Jack Wilshere is excited by the possibility of Rooney joining the Gunners.
"If it happens, it would be amazing," the 21-year-old told ESPN FC.  "He's the type of player who can win you trophies.
"Just to see his name on the team sheet brings fear to the opposition. We could do with a little more of that."
Phelan - who left Old Trafford this summer - admitted Rooney was not at his best last season, and the former United assistant manager added he does not know how the club's fans will respond to the forward in the light of his reported request to leave.
"That is a difficult one," he said. "You can put the first one [transfer request] down to inexperience but the second one is putting yourself right out there.
"Somewhere down the line there will be words said, there will be meetings and they will see if it's still alive and worth going for, or they'll call time on it.
"He's come from a fresh-faced 17-year-old and has been under the spotlight for that time and he has delivered. He might have hit a blip in certain performances but he isn't the first or last player to have done that.

Former United manager Sir Alex Ferguson persuaded Rooney to stay at the club in 2010 - handing the forward a new five-year contract - and Phelan revealed that the then manager was desperate to keep hold of the former Everton player."You have to nurse them through it and hopefully he responds to that. Sometimes you have to crack the whip with him. Wayne has responded as well as he feels he can do for United, and what will be will be - I haven't got a clue."
Phelan said: "Every player is entitled to express a desire to want to move on. Any player can do that at any time.
"In Wayne's case, in the first instance in 2010, he took a lot of advice on that and got steered towards making that call but the manager was terrific. He talked to him and asked why would he want to leave the club.
"The press conference Sir Alex gave was a bit of a tear-jerker and it was genuine. There was an element that he'd chased this boy and paid big money. He was the boy that could change United."
Speaking about his own future, Phelan said he was prepared "to go outside his comfort zone" to explore opportunities in the lower leagues.
When asked if he would like to take the step up to being a manager, he replied: "Yes, I would like to. It has always been something at the back of my mind.
"I know a lot about the Premier League and Europe, as that is where I have pitched myself. You now go outside your comfort zone a bit, and look at the level down or the level even lower than that.
"I am quite relaxed about the next phase of my career, but it is strange knowing in the next few days you will not be going back to work.
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