Watch: Messi bloodied by elbow to the face from Marcelo

Intentional, or just an errant elbow? You be the judge.

Lionel Messi was left in a bloodied heap early in Sunday's El Clasico, as the Barcelona magician was on the receiving end of an elbow to the face from Real Madrid left-back Marcelo.

The incident looks to be unintentional, though when it comes to this typically fiery rivalry between the two Spanish juggernauts, you can never be 100 percent certain.