The Group of Death is such that one slip-up and the chances of qualifying from the group stages could be gone. Real Madrid and Borussia Dortmund will be well aware of that factor as the Spanish champions and the German league winners lock horns in an intriguing battle in the Champions League.
Dortmund will be kicking themselves to not have six points, instead of four, on the board after throwing away a victory against Manchester City in the dying moment on Matchday Two. Real, on the other hand, are going from strength to strength, impressing in their comfortable 4-1 win over Ajax to maintain their perfect record.
Real face an injury crisis at fullback with left-backs Marcelo and Fabio Coentrao missing while right-back Alvaro Arbeloa is also injured - all picked-up on international duty with their various countries.
"It will certainly be a difficult match but not because of our injured players -- I don't think we are desperately short of players," Real manager Jose Mourinho said. "We will have a team capable of putting in a good performance here.
"It will be a difficult match because Dortmund are difficult opponents. The entire group is tough. You will not storm through this group by winning your first three games. Nor is it a group where you will break records and win 18 points."
Mourinho shifted Sergio Ramos at fullback for the game against Celta Vigo with defensive midfielder Michael Essien filling in the other slot. The same can be expected for Wednesday's game, unless one of the fullbacks pass a late fitness test, which is highly unlikely -- Marcelo is ruled out for several months, after breaking his metatarsal.
Real have not traditionally done well against German teams, but Mourinho is hopeful of a better performance against Dortmund. "The reason Madrid have not thrived historically in Germany is down to the quality of the opposition," he said. "If they did not come from a country with a strong footballing tradition, it would be different.
"I saw that last season when we lost the semi-final 2-1 at Bayern, but this record will not have a psychological impact. It is always a difficult task here in Germany, as they have strong teams with ambitions similar to our own.
"That's how things are -- German teams are always strong. We know how dynamic they are, how gifted and how quick they play, but they do have little weaknesses which we plan to exploit. We are not that worried about individual players, even though we know they have lots of good ones."
Despite the injury worries for Real, Dortmund manager Jurgen Klopp expects a tough outing against the Spanish champions, and will be banking on home advantage to get them a positive result. "It is a huge challenge," Klopp said. "I have watched Madrid a lot, and I saw them in Amsterdam where they put in a huge performance. They were tactically disciplined, quick, showed anticipation, pressed and counterattacked while playing football of a high technical standard.
"That left quite an impression. I have seen Real Madrid a lot but hardly ever this good. They have some injury concerns -- Marcelo was outstanding in that match but will not be available.
"We will have to work extremely hard without the ball, as we did at Manchester City. We will also have to get stuck in against some of their key players. If you play Real Madrid and don't get a grip on Xabi Alonso, you are going to have a problem. If you don't watch Ángel Di María, you are going to have a problem. If you let Cristiano Ronaldo attack at speed, you are going to have a problem.
"In Manchester, we felt how strong we can be if we perform the way we can. We have ways of making life harder for our opponents than they might expect. That will be our task. Whichever opposition player has the ball will receive special attention."
For Dortmund Marcel Schmelzer and Mario Gotze are expected to be fit after missing the weekend's game against Schalke, while Ilkay Gundogan remains a doubt.
Expected lineups: Dortmund: Weidenfeller, Bender, Subotic, Hummels Piszczek, Kehl, Grosskreutz, Leitner (Felipe Santana 89), Gotze, Reus, Lewandowski.
Real: Casillas, Ramos, Varane, Pepe, Essien, Alonso, Modric, Ozil, Di Maria, Ronaldo, Benzema.
Prediction: 1-1
