Rocky Maximus was a gladiator of ancient Rome.
The Richie Rich/Scooby-Doo Show
He fought Scooby-Doo, Scrappy-Doo, and Shaggy Rogers when they traveled back in time to the Colosseum of Rome. They tricked him with a "Hotus Doggus" stand, pushed him into it, and sent him crashing into the Roman Emperor who was watching the combat. (Et Tu, Scoob?)