"It's difficult but exciting as well because it's a group of a very good level," the manager said. "We have played Dortmund two years ago. We did well against them and Napoli did well last year.
"Marseille we played two years ago as well. It's a similar group to what we knew two years ago.
"Every game will be of huge importance because it could be down to a point or goal difference in the end."
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