Credit: Helene Wiesenhaan/; Jon Kopaloff/FilmMagic; Steve Granitz/

Brad Pitt pimped Jonah Hill's ride!

When the two teamed up to film Moneyball in the summer of 2010, actor Keith Middlebrook says Pitt, 47, pranked Hill by giving his set of wheels a makeover.

"This one time, for fun, he painted Jonah Hill's golf cart bright pink," Middlebrook tells "He had the faces of Wham!, George Michael and [Andrew Ridgeley], painted on his golf cart."

To up the ante, Pitt added pink balloons to Hill's tricked-out golf cart. "When you put the gas pedal on, it played the song "Wake Me Up Before You Go-Go,'" Middlebrook adds. "I'm still cracking up about it! It was just total chaos."

Funnyman Hill, 27, didn't seem the least bit fazed by Pitt's on-set prank. "Of course Jonah was cool with it," Middlebrook recalls. "He was cruising in his pink golf cart with Wham! painted on the side of it with balloons."

When Pitt wasn't playing practical jokes on his costars, Middlebrook says Angelina Jolie's longtime love spent his downtime entertaining sons Pax, 7, and Maddox, 9.

"The one kid, he's got his fatigues, and this kid's ready to take Afghanistan by himself," Middlebrook jokes of Pitt's brood, who were often seen playing with toy guns on set. "Pax and Maddox are hardcore!"