Watch: Broncos S Kareem Jackson delivers questionable blow to Vikings QB Joshua Dobbs in first game back from suspension

Three plays into the game, Jackson sniffed out a Dobbs rush around the corner on third-and-1, arriving with a pulverizing hit to force a fumble. Before making contact, though, Jackson lowered his helmet into Dobbs' chest, just under his chin, which led to a trip to the blue medical tent for the QB. 

Officials didn't throw a flag on the play and after an examination, Dobbs returned to the game no worse for wear. Only looking at the result misses the point, though.

The NFL has cracked the whip on dangerous hits to the head and neck area, especially those from players leading with their helmets. Furthermore, Jackson is a repeat offender and has received discipline several times this season alone. 

Jackson has been ejected twice this season for delivering hits to the head, with the most recent incident occurring in Week 7 when the Broncos safety launched himself into Green Bay Packers tight end Luke Musgrave. Jackson was suspended four games for the incident before the league reduced it to two games following an appeal.