Borussia Dortmund will need to check Real Madrid's early Champions League momentum when the top two in Group D face off on Wednesday with the Germans facing an injury crisis and poor form.
Security is an issue for the arrival of the Spanish giants in the wake of Saturday's riots in Dortmund before Schalke's victory in the Ruhr derby.
In total, 180 arrests were made with 11 people injured, including eight police officers, after violent clashes between rival fans.
Dortmund have big injury concerns with midfielder Jakob Blaszczykowski definitely out, while defender Marcel Schmelzer, plus midfielders Mario Goetze and Ilkay Gundogan are all racing to be fit to face Madrid.
"Jakub Blaszczykowski will not be ready in time, whether the other three are available again, I do not yet. Each day helps," said Dortmund coach Jurgen Klopp with Real top of Group D after two wins.
The trio was missing on Saturday when Dortmund crashed to the 2-1 home defeat against neighbours Schalke to leave them with just one win in their last six games. There was some good news for Klopp on Monday as Poland defender Lukasz Piszczek has extended his contract with the German champions until 2017.
"He is the driving force of our game," admitted the Dortmund boss.
The high-profile clash has extra significance with both teams having made a patchy start in their domestic leagues and desperate to do well in Europe to compensate for their domestic stumblings.
Dortmund have beaten Bayern Munich to the Bundesliga title for the last two seasons, but the Bavarians are currently 12 points ahead of Klopp's team in the league. Likewise, Real are eight points adrift of leaders Barcelona in La Liga.
With Real top of the group, second-placed Dortmund need to take points off the Spanish giants to keep their hopes of reaching the knock-out phase alive after a win over Ajax was followed by a 1-1 draw at Manchester City.