With Real Madrid trailing 1-0 in the second half, Ronaldo had broken free and looked to be in a good position to tie the match. Contact from behind sent Ronaldo to the ground, but no foul was called and no penalty kick was awarded. Here is the controversial no-call...
Here is another angle that makes it look like it should have been a foul...
Ronaldo certainly thought it should have been a foul...
Alexis Sanchez would later score on this gorgeous chip shot to give Barça a 2-0 lead. Real Madrid would add a late goal in the 90th minute but it was too little, too late...