Greatest Heavyweights is a boxing video game that was published by Sega in 1994. It was released for the Sega Genesis console. It is a follow-up to Evander Holyfield's Real Deal Boxing, and is virtually identical in many ways, apart from a number of significant improvements. The game features eight of the most famous and successful heavyweight boxers in history: Muhammad Ali, Jack Dempsey, Joe Frazier, Larry Holmes, Evander Holyfield, Joe Louis, Rocky Marciano, and Floyd Patterson. There are also a total of thirty other imaginary fighters present in the game. The cartridge supports the 6 button control pad (an improvement over the controller options of its predecessor).