Rulon Gardner won gold in wrestling in arguably the biggest upset in Olympics history ... and now the American hero, who's 51 years old, tells TMZ Sports he's making a comeback, and the goal is the Summer Games!
"I still wanna give more back to the sport, the sport that I love and that's wrestling. When you have a goal like wrestling it makes you get into shape so I've lost a substantial amount of weight, getting healthy again, getting back after it, and now it's getting on the mat," Gardner said.