No, Pettis was getting pieced up. The leg kicks appeared to have little to no effect on Wonderboy.
Still, it highlights that need to put your opponent away as soon as possible. If you let them hang around, any errant punch can end the fight. Striking is like that. It's why grappling is more reliable, and less prone to chance. Any idiot can throw a punch, and end your night no matter how good you are at striking.
It also highlights the importance of boxing over kickboxing. Wonderboy left his hands down, like Machida, and like Chuck and he paid for it. Karate influenced kickboxing is not good at defense, and it's punches are not powerful. Defense is crucial when striking, and it's why Karate is not a reliable striking style, and few can make it work. It requires exceptional reflexes, but leaves its user wide open for standard boxing counters.