Wednesday's preseason friendly between Roma and Barcelona was anything but friendly after Lionel Messi headbutted Roma's Mapou Yanga-Mbiwa.

During the 35th minute, Messi and the Roma defender got nose to nose before the Barca striker attempted to headbutt the much taller Yanga-Mbiwa.

Messi, considered by many to be the world's best player, is usually fairly congenial with opponents on the pitch, but clearly took issue with Yanga-Mbiwa initiating contact with his own head. Not only did Messi, 28, attempt to headbutt Yanga-Mbiwa, he then put his hand around the 26-year-old's neck. Neither player was carded for the incident, but had the match been a truly competitive game, both likely would have been sent off with red cards.