Borussia Dortmund achieved their biggest European win, hammering Polish champions Legia Warsaw 6-0 away from home to get off to the perfect start in their Champions League Group F campaign on Wednesday.Mario Goetze led the Germans' rout, opening the scoring and also assisting on two goals on a miserable night for the Poles that was marred by crowd trouble with home fans involved in fighting.Dortmund dominated from the outset with Goetze finishing off a cross from youngster Ousmane Dembele after just seven minutes.Fans of the first Polish team in 20 years to reach the Champions League group stages, who packed the 28,000-seater stadium in Warsaw, quickly turned silent as Sokratis Papastathopoulos and Marc Bartra scored within the next 10 minutes. Dortmund visibly slowed the pace of their attacks in the second 45 minutes but still effortlessly scored another three goals through Raphael Guerreiro, Gonzalo Castro and star striker Pierre-Emerick Aubameyang.The easiest of wins saw Dortmund take an early lead in the group on goal difference ahead of Real Madrid who beat Sporting Lisbon.In the stands, a group of hooligans wearing balaclavas tried to break into the Dortmund sector from Legia's side in the first half, and ended up fighting and spraying gas at the security guards...