Bayern Munich will start 2015 with a record 11-point lead in the Bundesliga, sparking debate over how to stop Germany's top flight becoming boring.

Pep Guardiola's Bayern has brushed aside domestic rivals with ease and is poised to become the first team to go through a Bundesliga campaign unbeaten on its way to what would be a third consecutive title.

Bayern set more records in Friday's 2-1 comeback win at Mainz, having conceded just four goals since August. Its points lead at the season's halfway stage is also a league best.