Mike Mitchell should draw a hefty fine for this one. There are some late hits that are borderline, and the rusher would have a hard time letting up, or where helmet contact occurs inadvertently.
This is not that. Alex Smith pulled a Houdini act on the blitz, with Mike Mitchell just missing him. Smith was able to escape up in the pocket and get the ball to Kareem Hunt. Well afte the release, Mitchell–frustrated by missing the sack–not only hit him, but dove low right at his knees from behind, upending Smith in a flying heap.
That drew an emotional reaction from Smith, and a “what did I do?” expression from Mitchell, laughably. I hope he makes the same expression when he gets fined this week.