What Han Sen had just performed was not exactly like Bai Yishan's Yin Yang Blast. It was a modified variant which employed twists Han Sen had decided to incorporate himself. One new component was a simulation of Bao'er's energy flow.
Yu Tuoshan's punch was supposed to hold the power of a bulldozer, which should have annihilated his opponent. And in essence, it was. Through a simulation of Bao'er's energy, Han Sen was able to absorb all of the strength the shura had put into his strike and reverse it. It was very promptly returned to the sender.
Still, this should have come as no surprise; after all, the skill was based on Yin Yang Blast.
The royal shura was strong, and he hadn't been wholly defeated yet. After crashing into the audience, he stopped for a moment to get a sense of what had happened, and then immediately hopped back into the arena.