Messi was celebrating Barca 's 94th - minute winner from Sergio Busquets with his team mates near the corner flag on Sunday when someone threw the bottle from the Mestalla stands .
Barca struck Messi on the head .
Messi was celebrating Barca 's 94th - minute winner from Sergio Busquets with his team mates near the corner flag on Sunday when someone threw the bottle from the Mestalla stands and it struck him on the head .