Cahill, literally twice the age of Arzani at 38 vs 19, has taken the teen prodigy under his wing at Russia 2018 and is constantly challenging the youngster to spur him on.

And at the end of what seems like every training session now, the pair will battle it out together as Cahill teases the best from the wing sensation, often ending in a grappling match.

See the pics above as they literally (play) fight for the ball before coaches finally end the fun by insisting they return the balls to them.

But the tussle still carried on even without the ball as the pair grappled in the dugout while bemused coaches watch on...