Real Madrid will have to go all-out against Barcelona if they want to overturn their first-leg defeat at the Santiago Bernabeu and advance to the Copa del Rey semifinals. In that vein, they're playing a creative attacking lineup that features both Kaka and Mesut Ozil (although Pepe's playing in the centre of defence just in case Lionel Messi needs a good kicking or anything).
Barcelona's response? Their standard 4-3-3. It's worked against the supposed genius of Jose Mourinho the last nine times they've tried it, so why change a winning formula. Hopefully Madrid's changes will make this Clasico more fun than most.