United took the lead in the ninth minute through Marouane Fellaini, before Michael Carrick headed home to double their advantage 10 minutes later.
And captain Wayne Rooney wrapped up the three points when he fired in in the 34th minute to keep Manchester United in fourth place in the Premier League table and a point behind Arsenal.
Rooney was one of the first United players to take to Instagram after the game, with the United skipper posting the picture above on the photo-sharing app and writing: “3 points. Job done.”
Midfielder Daley Blind, meanwhile, shared the picture below on his own account and wrote: “Very important win! A great feeling and a great team spirit today! #MUFC”
And goal-scorer Carrick posted the picture below of his goal celebration at Old Trafford, along with the caption: “Big win..A goal… and a Happy 7th birthday to my little girl Louise. As weekends go…”
Manchester United’s next game is a trip to Liverpool in the Premier League on Sunday.
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