The playmaker has fallen dramatically out of favour at Old Trafford in recent weeks and has been left out of seven of the last eight matchday squads by Jose Mourinho.
Mkhitaryan had initially made a strong start to the season under Mourinho but his form tailed off quickly following his strong start.
With the Armenia international currently out of favour at Old Trafford, there have been suggestions that his long-term future at the club is in doubt.
However, Arsenal legend Smith reckons that there is still time for Mkhitaryan to work his way back into the first team at Old Trafford this season.
Speaking to Sky Sports News on Friday, Smith said: “He has not been playing well enough but maybe the system doesn’t suit [him].
“He [Mourinho] has been relying on the likes of Anthony Martial and Marcus Rashford in those wide positions. Jesse Lingard has also been showing good form.
“Mkhitaryan hasn’t been playing well enough. He is a very talented boy but is yet to show us on a consistent basis what he showed at Dortmund, for instance. I don’t think Mourinho will be giving up on him just yet.
“It shows the depth of their squad really in terms of talent, that he hasn’t made the matchday squad a few times.”
Mkhitaryan will be hoping to feature for Manchester United when the Red Devils return to Premier League action on Sunday with a trip to the Hawthorns to take on West Bromwich Albion.
The Red Devils are desperately trying to get themselves back into the title race after having fallen way behind leaders Manchester United following their defeat by the Citizens last weekend.
Manchester United have not won the Premier League title since their final triumph under Sir Alex Ferguson in 2013.
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