The Italian, allergri, who ended Tottenham's dreams of Champions League glory at Wembley in midweek was linked with Arsenal last year before Wenger's FA Cup triumph earned him a new two-year contract at the Emirates.
The Gunners go into the tie with a commanding 2-0 lead from the first leg after a dominant performance at the San Siro.
The 29-year-old found himself frozen out by United manager Jose Mourinho, but Wenger is more appreciative of his qualities and has installed him on the right of his three-man attacking midfield.
Arsenal manager Arsene Wenger is anxious by an apparent dip in attendance at the Emirates stadium in recent weeks but said he is confident the team will do "absolutely everything" to win back their fans. "Hopefully our performances on the pitch will encourage everyone to come back", the Wales global said.
Arsenal's next game is on Thursday against AC Milan in the second leg of their last-16 tie in the Europa League at the Emirates, with the score now 2-0 to the Gunners.
Wenger revealed some of his players underwent tests this morning but he only has Alexandre Lacazette missing through injury.More news: Duterte withdrawing Philippines from International Criminal Court
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Alexandre Lacazette will miss the match following knee surgery, but is expected return to action following the global break.
"To do what they've done, people can say it's Scottish football and Celtic are head and shoulders above, but every team they played on that run treated it like a cup final, which is hard sometimes". They still, however, remain a long way from the dominant team they were over a decade ago.
With that in mind, Mkhitaryan's presence at the Emirates Stadium might be seen as a good omen for Wenger. It was quite a tight game even though we came away with a 2-0 victory.
The Gunners faithful have been given renewed hope of another man leading their side after Frenchman Patrick Viera claimed he would hope to return back to Arsenal. "We can't take this one lightly at all".
Nicholas believes Wenger should try to go out on a high and should announce his intentions if Arsenal proceed to the quarter-finals of the Europa League.
A third straight win would also allow them to enter an extended global break on a bit of a high after one of the roughest spells of Wenger's 21-year career. You pick the best team to win the next game.