George Clooney at the Oceans 13 Las Vegas Premiere at the Opening of CineVegas held at Palms Hotel Casino. Las Vegas, NV - 06.05.07

Clooney, who directs and stars in Leatherheads, was surprised by the 27-year-old's cocky confidence.

The 46-year-old says, "I love him, but the fun part is that he talked s**t.

"The first day on the set he's like, 'I play basketball' and I was like, 'I play a little too.' He looks at me and goes, 'I'll kick your ass.'

"And I was like, 'Alright, whatever.' And he's like, 'OK, let's make it $1,000 then.'

"So for the entire shoot we've been talking about this bet. We haven't played, the whole shoot. And (on the last day of shooting) we played. And I beat him 11-8!

"I was on cloud nine. I was wiping my forehead with $100 bills going, 'Whooo, is it hot in here?'"

Source: WENN