Portugal and Germany are losing players left and right. The Portuguese have already lost three -- Hugo Almeida and Fabio Coentrao to injury, as well as Pepe to a red card suspension -- and now Germany have lost one of their own. Mats Hummels has injured his left knee, and could not put any weight on his leg as he was carried off the pitch.
Defense has been a bit of a problem area for Germany. Not necessarily central defense, where Hummels plays, but fullback. They have no depth at the position and have been forced to move Philipp Lahm into midfield due to injuries there. They started this game with four center backs, and will keep playing four center backs -- Shkodran Mustafi has taken Hummels' place, and might play right back even though he never plays there.
This is all very good for fans of the United States, but it's a shame so many good players are going down.