Bayern Munich extended their lead on top of the Bundesliga after beating Karlsruhe 2-0 as nearest challengers Werder Bremen slumped to a stunning 6-3 defeat to Stuttgart. At Allianz Arena, Italian in-form striker Luca Toni opened the scoring four minutes before the break with a precise shot. French winger Franck Ribery sealed the victory in the 64th minute after a brilliant individual effort. Elsewhere, title holders Stuttgart dented Bremen's league hopes in a thrilling match. Hugo Almeida put Bremen in front after nine minutes but Mario Gomez scored twice to turn the match into the hosts' favor. Sebastian Boenisch grabbed the equalizer on the hour mark but Gomez completed his hat-trick in the 65th minute to restore Stuttgart's advantage. A Cacau strike and own goal by Per Mertesacker either side of Markus Rosenberg's consolation gave Stuttgart an impressive win. Bayern remain on top of the league table with 50 points, seven clear of second-placed Bremen.