Arbeloa and Iker didn't shake hands on the bench

The relatationship between Iker Casillas and Arbeloa is fraught. Cameras from TV channel Cuatro caught the fact that the defender and the goalkeeper didn't shake hands when the former was substituted at Balaídos.
Curiously, Casillas did greet Khedira when the German took his seat on the bench, barely 10 seconds after Arbeloa walked past him.