Pearson doesn't look like the same fighter he once was
Of course he doesn't, what fighter with that many fight does? He has changed his style to take less damage and counter more. Hirota landed a lot of leg kicks but other then the two punches in round 2 he really didn't do any damage, leg kicks are a good tool but when that is all you do and your opponent walks through them it is unlikely you will get a decision. If he had been able to throw a knee when he had Pearson rocked in the second it would of likely ended the fight or at least put Pearson on the ground in a vulnerable position; it is hard to do though when you are thinking punches. I see more fights like this for the end of Pearson's career with guys he just a little bit better with that he can beat with experience, which is fine as I like watching him work.