​Henrikh Mkhitaryan failed to hit his best form at Manchester United due to a lack of 'freedom' under boss Jose Mourinho.

That is the verdict of United legend Wayne Rooney, who told Sky Sports' Monday Night Football programme (via the ​Mirror) that the Armenia international wasn't given the opportunity to showcase his talents in full.

Mkhitaryan only played for the Red Devils for 18 months before he swapped Manchester for north London as part of the deal that took Alexis Sanchez to Old Trafford in late January.

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Mkhitaryan's inability to due the deeds at United, however, should not fall on his shoulders according to Rooney, with the now ​Everton star admitting the 29-year-old was restricted in what he could do on match days.

The 32-year-old said: "I've seen it last season in training a lot, he's a very talented player. I think at ​Manchester United he didn't get the freedom he really wanted to go and perform, that he had at Dortmund and that style of play that ​Dortmund played.

"And at Arsenal he'll have players round him running off the ball, taking the ball and he'll create goals and score goals. I really do think he'll kick on."

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Rooney played alongside Mkhitaryan during his final 12 months with United, and locked horns with the forward at the Emirates last Saturday as ​Arsenal thrashed the Toffees 5-1.

The ex-Borussia Dortmund ace laid on three assists on his home debut for Arsene Wenger's men as Sam Allardyce's charges were blown away due to their defensive frailties.

Mkhitaryan is already just eight assists behind his total haul in United colours, but still has a ways to go to eclipse the 13 goals he struck for the current second-placed ​Premier League side.

Mkhitaryan will have the chance to further cement his place in the hearts of Gunners fans next Saturday if he can bag a winning goal in the north London derby against fierce rivals Spurs.