Arsenal beat Manchester United at Emirates in the 30th game of the Premier League.
The 3-0 away defeat was the first for Ole Gunnar Solskjaer's side.
Granit Xhaka opened the score in the 12th minute of the match and in the 69th minute Pierre Emerick Aubameyang scored the second from the penalty spot.
Arsenal are now in the fourth place of the Premier League table with 60 points, while the Red Devils are in the fifth with 58 points.
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