The final installment of the Arsenal-United feuds on our list came in 2004, when Manchester United put an end to Arsenal's 49-game unbeaten run with a famous 2-0 win at Old Trafford. After the match, Arsenal's players—reportedly wearing "50 Not Out" T-shirts under their kits—were still seething over a late disputed penalty. It all kicked off in the tunnel post-game, with Cesc Fabregas thought to have been the player who threw a pizza that hit Sir Alex Ferguson—to hear Ashley Cole tell it—"straight in the mush." Why oh why was this not caught on tape?

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