I have the Championship Boxing box and disk. It was given to me from my step father-in-law. I haven’t had a chance to try it out on my 486 IBM PS2 to see if it still works. I once ran an Alf game on that computer and it went so fast that I lost once I started the game.
The box shows a kangaroo on the back fighting a boxer. I thought there were newer games by other companies with the same characters. I think it was Fist of Furry?