When he was 23, Jesse Cole was general manager of the Gastonia Grizzlies baseball team in Gastonia, NC — and it was going badly. With only a couple hundred people watching the games and money fast running out, he decided to try something different to boost attendances, handing out whoopee cushions at Flatulence Fun Night and hosting a Salute to Underwear Night, where anyone wearing their underwear on the outside of their clothes gained free entry. Soon he added music, dancing and fireworks and went big on interactive fan experiences, like a Grandma Beauty Pageant and Dunk the GM in the Dunk Tank, and, sure enough, attendances went through the roof. “It was like going to see a circus but then a game of baseball broke out,” he tells The Post. The Savannah Bananas have revolutionized baseball with a fan-first approach: Bring the fun, and everything else will follow. Getty Images Unwittingly, though, the Grizzlies would prove to be the blueprint for his next, and most famous, creation — the Savannah Bananas .…