On Tuesday, Robert Klemko of The MMQB brought us the story of former Jaguars linebacker Russell Allen, whose career ended after he suffered an in-game stroke in Week 15 of last season. Above is video of the play that led to Allen's stroke.

Allen is wearing number 50 and is the middle linebacker on the left side of the Jaguars formation. What's disturbing about this is just how innocuous a play this was. Allen didn't get blindsided by a chipping tight end or leveled by a charging running back. He just got blocked, cleanly, like he had hundreds of times throughout his career. Allen wasn't even hit hard enough to lose his footing.

This is just another reminder that there's no real way to prevent head injuries in football. The game itself, even at its most basic and routine, is violent and dangerous.