The popular belief is that this change was made due to Mike Tyson being convicted of a crime in 1992. In actuality, Tyson's contract with Nintendo had expired; following his 1990 loss of the championship to Buster Douglas, Nintendo showed disinterest in renewal of his contract. Tyson had been slated to star in a sequel where he would be the playable character. It was this case as a result of his legal troubles all interest ceased, and the game was eventually released as Power Punch II with a generic character named "Mark Tyler".
For a limited time (until March, 9, 2014) Club Nintendo members can get a download code for 200 Coins.