Expectations were high for ex-Red Devil Danny Welbeck who played his first game against United since his controversial summer transfer to north London.
With numerous injuries United fielded an unconventional back three featuring a newly fit Chris Smalling and youngsters Tyler Blackett and Paddy McNair.
Arsenal dominated the first half with Welbeck coming close to scoring but for the safe hands of David De Gea. Worryingly for the away team Luke Shaw was clipped by Alex Oxlade-Chamberlain resulting in him being subbed off only 19 minutes in.
Neither side could break the deadlock though United were definitely more effective after the break.
It took a Kieran Gibbs own goal to put United in front and to make Arsenal chase a game they should have put to bed.
The situation got worse for Arsene Wenger’s men as a carefully timed pass from Angel Di Maria set Wayne Rooney up to score United’s second.
Five minutes into extra time super sub Olivier Giroud pulled one back for the Gunners but at the final whistle United had all three points and move up to fourth while Arsenal sink to eighth.
Click on Jack Wilshere to see just what we learnt from the Gunners this weekend.
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