Russell Crowe and Jimmy Fallon Rock Out to Earth Day Song ‘Balls in Your Mouth’ (Video)

The “Gladiator” actor also celebrates his rugby league team’s championship victory by throwing hats into the audience

Last Updated: April 22, 2015 @ 11:20 PM

Russell Crowe isn’t just an Oscar winning actor and blockbuster action star — he’s also a sports franchise owner and a surprisingly good singer.

The “Gladiator” star showed off his passion for the former and talent for the latter when he appeared on Wednesday’s “Tonight Show” with Jimmy Fallon.

In honor of Earth Day, the late-night host wanted to perform an acoustic song he’d written about the fifth anniversary of the BP oil spill. “Those tar balls are still washing up,” he lamented.

Because Crowe could “really feel” where he was coming from, he grabbed a guitar and sang the strangest political activist song ever.

“Balls in your mouth, balls in your mouth, don’t swim in the ocean you’ll get balls in your mouth,” the catchy chorus went as the pair rocked out on stage.

Earlier in the show, Fallon congratulated Crowe on the success of his Australian rugby league team, the South Sydney Rabbitohs, who won the championship last season.

And like a true fan, Crowe was still celebrating. “Bring out the hats!” he shouted as a box of memorabilia was hauled onto the stage.

“This means, that after a nine year process — we took them from being perennial losers to being dominant to being champions on the 5th of October for the first time in 43 years. South Sydney raised the trophy,” he proudly told Fallon.

After giving hats to the band and Fallon’s entire family, Crowe flung them out into the audience.

Despite having been born in New Zealand and growing up in Sydney, “The Water Diviner” actor is no stranger to New York City. “I’ve made quite a few movies here, I’ve been arrested here … I am little bit like part of the furniture,” he said.

“The Tonight Show” airs on NBC at 11.30 p.m.

Watch the video here.