Manchester United boss Jose Mourinho says Henrikh Mkhitaryan "has to play better" than his rivals for places in the first team if he wants to be given more minutes.
The 27-year-old Mkhitaryan was signed for £26m in the summer, having been one of the top performers in the Bundesliga during a three-season stint with Borussia Dortmund.
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However, his career at Old Trafford has yet to take off and, when he came off the bench on Thursday night in Fenerbahce, it was his first appearance for the United first team since he was taken off at half-time during a 2-1 loss to local rivals City back on September 10.
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United ended up losing 2-1 in Turkey, having already been 2-0 down when the Armenian was introduced, and Mourinho made it clear afterwards that the attacking midfielder has it all to prove.
"He has to do more, it's as simple as that," said Mourinho.
"We have big expectations at this club, lots of players for these positions, and he has to play better than [Juan] Mata, [Jesse] Lingard, [Anthony] Martial - he has to play better than them. It's as simple as that.
"Every manager wants to win matches, every manager in the world wants to play the players that he thinks can help the team more, and I'm no different."
The defeat dropped United to third in Europa League Group A, albeit just a point behind leaders Fenerbahce and Feyenoord.
Questions for Mourinho
Where is the cutting edge? What is up with Ibrahimovic? And will Mkhitaryan ever be ready?
Their next European game is at home to Feyenoord on November 24, which will follow key Premier League games at Swansea (November 6) and at home to Arsenal (November 19).