The Armenia international is currently getting used to life at Old Trafford following his summer transfer to the club from Borussia Dortmund.
Mkhitaryan initially struggled to have much of an impact at Old Trafford as he was hampered by form and fitness in the early stages of the season.
However, the playmaker has been in much improved form in recent weeks and has earned plenty of praise for his displays for Jose Mourinho’s men in the second half of the campaign.
And Smalling has lifted the lid on how he and his Manchester United team-mates struggle to keep Mkhitaryan quiet in training at Carrington.
Smalling told United Review: “He is often thinking one step ahead [in training], whether it is a pass or a dribble.
“He is deceptively quick as well and he is probably quicker with the ball than he is without, which is rare for a lot of players.
“He is a great, great asset for us.”
Manchester United return to Premier League action after the international break with a home clash against West Bromwich Albion as they bid to continue their march towards a top-four finish.
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