Since the start of last season Arsenal have scored 22 goals from corners, so their threat from set-pieces is hardly a hidden secret.
Mikel Arteta's team have become Premier League experts at converting from dead-ball situations, and both their goals against Manchester United came from corners.
So good are they from this position that the Emirates crowd were singing about 'Set Piece FC' towards the end of Wednesday's 2-0 win, while Jurrien Timber, scorer of the first goal, suggested the threat had become a mental one as well as a tactical one for opposing teams.
Even without centre-back Gabriel, who causes so much of the chaos that Arsenal's corners create, they continued to look a significant danger against United.
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