Manchester United and Manchester City have been duking it out in the Manchester Derby since 1881. For those who may not be aware, the rivalry is every bit as bitter, fierce, and intense as any other in the world of sports.On Sunday, the rivalry was renewed as the two locked horns for the first time this season. United came away with a 3-2 victory after Robin van Persie scored off a free kick in injury time. Things turned bloody during the celebration as a crazed City fan rifled a coin in the direction of United's Rio Ferdinand. Fortunately, the coin missed nailing Ferdinand directly in the eye but did manage to open up a nasty gash to the side of it. What a pitiful display of sportsmanship on the part of the City fan.So, next time someone tries to tell you that the craziest rivalry involves the Lakers-Celtics, Red Sox-Yankees, Duke-North Carolina, or anything else, think back to this.Via Total Pro Sports.