Bayern Munich have won all eight of their Bundesliga games so far this season, but the veteran coach is worried that overconfidence could be an issue
The Bavarians sit pretty at the top of the Bundesliga, crucially nine point clear of current champions Borussia Dortmund, having amassed eight wins on the trot.
However, the 67-year-old has warned them not to underestimate their opponents, who are in a good run of their own of late.
"They are in very good shape at the moment," he commented at a press conference. "They play flowing, attractive football and they are very skilful.
"We would be well-advised to keep our feet on the ground, approach it professionally, and not rely on statistics. Instead, we should carry on doing what we've been doing in the league so far."
Club captain Philipp Lahm echoed his coach's thoughts regarding the upcoming encounter, maintaining his team-mates would have to be on their toes when entertaining the Werkself.
"From the start, we must be wide awake," he insisted. "Leverkusen are a dangerous team. "However, if we impose our authority on the game, there can only be one winner, and that will be us."
The trio of Franck Ribery, Daniel Van Buyten and Javi Martinez will be absent for the home side, who have been boosted by the return of Arjen Robben.