Manchester United 8-2 Arsenal
Where better a place to start than arguably the other most damaging defeat for an Arsene Wenger side, which sparked a very unusual trolley dash in the last few days of the transfer window in 2011.
What is often forgotten in this match is that Robin van Persie missed a penalty in the 27th minute which would have made it 1-1, then Ashley Young went up the other end immediately afterwards and popped one into the top corner.
Young Carl Jenkinson was sent off in the match and it also saw the Arsenal debut of Alex Oxlade-Chamberlain - probably not exactly how he imagined it. Wayne Rooney bagged a hat-trick, while Young hit another nice goal and even Park Ji-Sung got on the scoresheet.