Bayern Munich launched their bid to win an historic fourth successive Bundesliga title on Friday with a 5-0 rout of Hamburg as new signing Douglas Costa shone on his league debut.

Bayern's established campaigners Robert Lewandowski, Medhi Benatia and Thomas Mueller, who netted twice, grabbed Bayern's first four goals with Brazil winger Costa adding the fifth to seal a show-stopping performance. Costa, who Bayern coach Pep Guardiola has said can be the best winger in the world, showed why the champions paid Shakhtar Donetsk 30 million euros ($33.3m) for him in July.