If I put the hours I spent trying to beat Evander “Real Deal” Holyfield boxing on the Genesis into actually trying to box, I probably would have been a pretty decent fighter. If anything, I would have been in a lot better shape in my teen years.
The simple overview is that you start from the bottom and fight chumps as you try to build your rank. Between fights, you can choose from various bonuses that will elevate the various skills that pertain to your boxer (power, stamina, speed, defense). Eventually, you fight the champ himself for all the marbles.
However, if you’d like a leg up on the competition, enter “The Beast” as your name in career mode and you’ll become this freak of nature with full stats: