The BVB goalkeeper is delighted with the DFL-Supercup victory and believes it was important to dent the Bavarians before the start of the new seasonRoman Weidenfeller has stressed the importance of Borusssia Dortmund proving Bayern Munich are beatable following their 4-2 DFL-Supercup victory on Saturday.
A double by Marco Reus, an Ilkay Gundogan strike and an own-goal from defender Daniel Van Buyten ensured the Bavarians were defeated at Signal Iduna Park in Pep Guardiola's first competitive match for the club.
BVB goalkeeper Weidenfeller is convinced it was important to demonstrate that the treble winners can be stopped ahead of the start of the 2013-14 Bundesliga campaign.
"It was important that we demonstrated that Bayern are beatable," he told Bild. "If we lay down a solid plan, we have a chance against any team.
"Against Bayern, we pressed very aggressively from the beginning. They attacked us early as well, but we did well to free ourselves and make the switch into attack with our fast players."
Jurgen Klopp's men kick off their Bundesliga season with a trip to Augsburg on August 10.