VIDEO: Fan pours beer on Celtics draft pick Thornton during game in Australia

SYDNEY - An Australian basketball fan faces a possible life ban after tipping beer on the head of Boston Celtics 2015 draft pick Marcus Thornton during a domestic league game.

Thornton was playing for National Basketball League side the Sydney Kings against the Illawarra Hawks on Wednesday. Driving to the net in the third quarter, the 22-year-old American fell to the floor and slid on his back into the edge of the court before a man leaned over sponsors' signage and poured his drink over Thornton.

Live footage showed the fan continued to drink his beer while a female companion berated him. They were escorted from Wollongong's WIN Stadium a short time later.

NBL officials are expected to investigate and the man faces a possible life ban or suspension.