Arsenal boss Arsene Wenger has made a glowing tribute to German football.
Ahead of the trip to Dortmund on Tuesday, Wenger said there was no better classroom.
"Maybe there the football roots are the deepest in the world," said the Gunners boss. "Schalke, Dortmund, Borussia Monchengladbach - this is the triangle in German football.
"When I was a kid, we had eight teams in the Bundesliga within 100km. You had Schalke, Dortmund and Monchengladbach. Dortmund now have 80,000 people at every game.
"They have a similar style to us so it will be a very interesting game."
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