Looks like a clipped pedal caused the rear wheel to slide. Then the rider tried to correct and went high side. It could be the sliding wheel caught a crack or something in the pavement sending him high side. Always hard to watch a crash. Hope the grass was soft enough that he came out with just scrapes.
Yep, looks like they catch a pedal and slide, save it but the sudden grip high sides them. Almost rode it out thoug .