Oh boy. That right there, via Royce Young, is Caron Butler violently blocking Serge Ibaka's shot directly into the face of referee Derek Richardson from about four feet away. Richardson took a spill, but salvaged the wherewithal necessary to make the correct possession call and hop to his feet.
We often marvel at the pain tolerance of professional athletes, but these refs are pretty tough, too. If it were me, I'd still be crying right now.