Borussia Dortmund have the potential to put Bayern Munich under a lot of pressire in the Bundesliga title race this season, according to Ottmar Hitzfeld.
Bayern have walked to the league title in each of the last two seasons, finishing 25 points ahead of Dortmund two seasons ago before ending up 19 points clear come the end of last season.
However, the 65-year-old, who coached both clubs in his career, believes Dortmund could mount a serious challenge this term if Bayern don't start well.
"Dortmund must score, score, score," Hitzfeld told Stuttgarter Zeitung. "With a super start, you can make Bayern nervous.
"If Dortmund pulls away and Bayern experience a stuttering-start, they are criticised. The players who are not nearly as tough read this [in the media]. Then they will still be nervous and then Dortmund would have a chance.
"For Bayern coach Pep Guardiola it is a Herculean task. He should make up the strongest team, but must pay attention to his national team and their level of performance.
"This requires a lot of tact. Jürgen Klopp in Dortmund is similarly challenged."
Bayern face Wolfsburg in their league opener on Friday, and Philipp Lahm insisted the champions are still confident despite Thiago, Javi Martinez, Rafinha, Bastian Schweinsteiger and Jerome Boateng all missing through injury.
Lahm said: "We are not afraid. Our team can be still seen. Many are waiting for us to lose.
"We do not like it when others are ahead of us."