The answer could reasonably have been Floyd Patterson, due to his smallish stature, or the proliferate, and still well known Archie Moore. However, Tom Burns, all the way back in 1908 seems to be one correct answer, although most, including me, have never heard of him. I'm sure Michael Spinks is equally and much more notably a correct answer as well. As a young professional Michael Spinks was noted as having the legs of a Heavyweight and the upper body of a Middleweight. Only later, those still only 208 lbs at his heaviest, did he become a true Heavyweight, with the goal of defeating long reigning champion Larry Holmes. After a couple of highly disputed decisions, Spinks obtained his Heavyweight dream. I watched both fights on CTV as a young amateur boxer and I believe Holmes won both bouts hands down. Holmes had alot of forces against him going into the matchup. He would have eclipsed the famed and widely revered record of Rocky Marciano and while maybe the best Heavyweight ever he was not built like the ideal athlete, many considered his style to be boring and he lacked the vitality and charisma of Michael Spinks. Spinks was a world famous fan favorite, and Olympic gold medalist. Boxing was ready for a change and Spinks was it. Along with the Light Heavyweight to Heavyweight first, and the Olympic gold, Michael and former champ brother Leon, became the only brothers to both win World Heavyweight Championships. Michael holds one more record of lesser value. He became the fastest World Heavyweight Champion to be knocked out, when he was defeated by Mike Tyson in his final boxing match. I also watched this live on CTV, the precursor to PPV. It lasted a mere 91 seconds into the first round, just enough time for Tyson to land a solid blow. This was Michaels only loss, but also his financial savior. He still retains a chunk of his $13.5 million purse, while brother Leon makes minimum wage as a part time janitor after succumbing to drug and alcohol addiction.