Dortmund boss Mats Hummels believes his side can overturn 2-1 deficit . Klopp 's side have kept a clean sheet in their last three league games . The Black and Yellows have improved since the return of Jurgen Klopp .
Dortmund boss Jurgen Klopp believes his side can overturn 2-1 deficit . Klopp 's side have kept a clean sheet in their last three league games . The Black and Yellows have improved since the return of Mats Hummels .