Yes, players should be mandated to take anger management training prior to competing in high level sports. Since 1879 there have been thousands of incidents involving player attacks. This must change and fast. The recent Michigan incident needs to be taken as icing on the cake for a program to be instituted.
While this is a very scary and disturbing story, I don't think all athletes should be required to undergo anger management. We don't have nearly enough doctors if everyone would be forced to do this and it wouldn't even guarantee that bad incidents would never happen. I think coaches should monitor their players behavior and make the appropriate substitutions if necessary.
Just because of one isolated incident, should all sports necessarily suffer? Couldn't this then spread to schools, workplaces, and even family homes? It is not often that sports ends in death, so treat people as individuals, and don't lump them together and reuire anger managemnet until they show they need it.
While the case of the Michigan Soccer Referee punched and killed by a player shows the need for league commissioners to take hard line stances on ANY contract with an official, in the NFL it get you a one game suspension. It does not show the need for Anger Management training to be a requirement for playing competitive sports.