Pedro gets a yellow card in the 34th minute after he tangles with Ricardo Carvalho, hard to tell if the card was for the challenge or if Pedro said something after the play that the referee didn't appreciate.
Great chance for Ronaldo after a bad giveaway by Gerard Pique in the midfield allows him to streak down the right side and into the Barcelona box. Ronaldo's shot from 15 yards is saved well by Jose Pinto and it's another wasted chance for Madrid, who've dominated the entire half so far.
Barcelona looks toothless on the attack so far today as Madrid's plan has worked to near perfection, with the exception of their finishing which is betraying Los Blancos. You'd have to think Barca will be happy to get to halftime with the match scoreless at this point.