Real Madrid will make the difficult trip to Germany this week when they take on Borussia Dortmund in the first leg of their Champions League semifinal.
Having played twice already in the group stages of the competition, both teams will have a very good idea of what the other team is capable of and what potentially lies ahead in the next two legs, but there's still plenty that we don't know about this fixture.
Jose Mourinho and Jurgen Klopp are both brilliant attacking managers in their own right, and will no doubt have prepared their teams to play very well here.
But which team will emerge victorious?
Well, that we won't know until Wednesday afternoon, but what we do know is that there's plenty of key talking points heading into this one.
And whilst they might only be storylines, they do allow us to gain great insight as to who might be walking away victorious from the Westfalenstadion.
Read on to see the top storylines for this key semifinal matchup.
Can Real Madrid Win the Counterattack Battle?
Throughout the two group stage games that they played, both sides saw plenty of key chances on the counterattack, and it seems more than likely that they'll do the same throughout the two legs here.
Dortmund showed against Malaga how deadly they can be on the counterattack, and have portrayed those skills throughout the season. The same also goes for Madrid, who will know that swift ball movement to the left-hand side of Cristiano Ronaldo could reap huge rewards for them.
And playing away from home, it will be Los Blancos who pose the biggest threat in this one, for one away goal to them could be huge in the return leg.
Mourinho's men have shown to be great at moving the ball downfield all season, and will look to do the same here. Be that through Mesut Ozil in the middle, or Ronaldo and Angel Di Maria on the wings, they will be big threats on the fastbreak.
Dortmund showed in the two games they played against Madrid that they can close that down relatively well, with Mats Hummels key at moving across to either flank and adding extra coverage. If he can do that here, the home side will take away arguably Madrid's biggest weapon on the night, but if not, the away side will cause many problems for the Dortmund defense.
How Will Transfer Details Affect Mario Gotze and Dortmund?
Less of a raw football discussion and more ideological and psychological here, but don't rule out how important the Mario Gotze transfer details will be for Dortmund heading into this must-win game.
The Dortmund star was revealed yesterday (coincidental, I think not) to be joining Bayern Munich at the end of the season. Which is definitely not an ideal circumstance to be dealing with on the day before a high-profile match like this one against Madrid.
How that decision will affect Dortmund will be fascinating to see given that Gotze has been central to their attacking style and success this season.
He is a brilliant midfielder, but now leaving Jurgen Klopp's team for arguably their biggest rival won't sit that well with the team. Of course they're professionals, but it has to have some impact in this one.
Just how big of an impact it will be still remains to be seen.
It could have been worse: It could have happened a couple of hours before the game. But on a scale of one to 10, this is a nine.
We're hurt but this makes us even more determined. I don't know why they would release this now but if they want to make it so that we do not win, I can tell them that they will not succeed.
Will the Home Ground Advantage Carry Dortmund to Victory?
All season, Borussia Dortmund's home-ground advantage has been key to their success, and it will likely be an absolute nightmare for Real Madrid in the first leg of their semifinal matchup.
The Yellow Wall at the Westfalenstadion will no doubt be in full flight, and with five victories from their five Champions League performances at home so far, Dortmund will have a great advantage here. Especially given that Madrid aren't the greatest road team in the world.
Dortmund will likely use their home support—which could be even more powerful following the Gotze news—to gain a key advantage in the first leg.
They'll know that travelling to the Bernabeu won't be easy, and that Madrid will get a big advantage playing there. And they'll know—having been there already this year—that without an aggregate lead, Los Blancos will be very tough to keep out of the 2013 Champions League Final.
Can Dortmund's home-ground advantage give them victory this week?
We'll find out soon enough.
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