It's been fairly simple for Real Madrid so far, with Lyon failing to provide a great deal of opposition in their 2011 UEFA Champions League Round of 16, second leg tie. Real Madrid only have one goal, but that's due to the brilliance of Lyon goalkeeper Hugo Lloris and a fairly conservative approach by Jose Mourinho. Madrid are not playing a defensive or negative style of play, but they have found exactly the right balance between creativity and organization thus far. Though Lloris has saved a few possible goals, Marcelo was able to find the back of the net in spectacular fashion, and his goal is the difference between the two teams.
In the second half, it wouldn't be the least bit surprising to see Jose Mourinho have his team set up in an even more defensive fashion, possibly bringing on Alvaro Arbeloa and moving Marcelo up into midfield. However, Marcelo looked like he may have picked up a slight injury at the end of the second half, so it's possible that he can't continue. Regardless, Cristiano Ronaldo and Karim Benzema are good enough to create chances by themselves, so Madrid can afford to put a few men behind the ball.