Bayern stand on the brink of securing their 24th German top-flight crown, and victory in Berlin will ensure that the runaway leaders cannot be caught by nearest rivals Borussia Dortmund, who are 23 points adrift.
A win would also clinch coach Pep Guardiola's third piece of silverware in his first season in charge at the Allianz Arena, having already added the UEFA Super Cup and FIFA Club World Cup to Bayern's bulging trophy cabinet.
Jurgen Klopp's second-placed Dortmund, meanwhile, side welcome local rivals Schalke, who are third, to Signal Iduna Park, with only a point separating the two teams.
Dortmund's inconsistent season is highlighted by the fact that they have only won twice in their last seven home Bundesliga matches.
"The goal is as before, to qualify for the Champions League," said Keller. "In this regard Schalke are in a very good way.
"However, we must keep a cool head.
"We're playing a very, very good second half (of the season) and know our strengths."
Schalke have opened up a six-point gap on Bayer Leverkusen, with Sami Hyypia's men hoping to end a run of six games without a win when they face Augsburg on Wednesday.
Borussia Monchengladbach are poised to capitalise on Leverkusen's form slump and could leapfrog them in the table if they beat Eintracht Frankfurt.
