The Armenia international, back in the United side after recovering from a hamstring injury, hit in the first half to liven up an otherwise underwhelming Europa League encounter.
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And his strike in the Russian city drew him level with Wayne Rooney in scoring in at least three straight matches on the continent.
Rooney had been the last man to achieve the mark for United, all the way back in March 2010.
In the 2009-10 Champions League, the striker netted twice at San Siro in a 3-2 last-16 victory over AC Milan, and added two more in a rampant 4-0 win back at Old Trafford.
He went to score in the Allianz Arena as United went down to Bayern Munich 2-1, a tie which the Premier League club lost on away goals against the eventual runners-up.
