A fight with Lara would be competitive, or at least possibly dangerous. We have to look at the styles. Marquez took a while, but timed Manny perfectly. Floyd still has those cat like reflexes and it would take him 2 rounds max to adjust to Manny's reckless pressure fighting coming in with 1,2's it's consistent and easy for many guys to time, even Bradley who isn't a power puncher hurt him with a shot much the same way. Floyd isn't a puncher because he doesn't want to break his hand again, and also because he doesn't really sit down on his punches because it takes away from his defense, but early in his career he was in fact known as a power puncher, but this was at 122 or 126... I forget which... point being is that if he wanted to get more KO's he could. Many guys also get KO'd trying to get KO's, so it's not always wise.
