Seems like one of those plays that looked worse than it really was. Both Rising and the defender were running full speed to the sideline. You see the defender trying to let up and he lets Rising go after initially wrapping him up. Then whether intentionally or not, he does push Rising in the back. To me it looked like self-preservation as he was about to go crashing into the coolers. If it was intentional it wasn't much. It almost looked like he might have been thinking about holding Rising up and then bailed.

A flag would have been justified — there was a push, and the intent generally doesn't matter with personal foul calls. But this was definitely not a dirty play. I don't think even Ute fans would be calling this a dirty play had Rising not been injured.