The Armenia international was in fine form at the King Power Stadium and scored the opening goal on the stroke of half-time as he raced clear of the Leicester defender and slotted home.
Zlatan Ibrahimovic added a second shortly after, before Juan Mata made it 3-0 in the second half.
The result was a welcome one for the Red Devils after three successive draws in the Premier League and left the Red Devils a point behind fifth placed Liverpool.
And Carragher was particularly impressed by Mkhitaryan’s pace shown in the build-up to the opening goal against the Foxes.
Carragher told Sky Sports after the game: “He’s got something that very few players have in his position – and that’s pace.
“You think of Juan Mata, Mesut Ozil… great technicians but they don’t have that pace. It was vital for the first goal.”
Manchester United now turn their attentions towards their home clash against Watford in the top flight next weekend as they look to continue their push for a top-four finish.
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