DETROIT -- A weekend soccer player in the Detroit area whose punch killed a referee has been sentenced to at least eight years in prison for involuntary manslaughter.

The case against Bassel Saad has put a spotlight on out-of-control recreational athletes and inspired Michigan lawmakers to consider new crimes for assaults on sports referees.

Saad, an auto mechanic, admits striking referee John Bieniewicz during a game last summer. Bieniewicz was preparing to call a penalty that would have ejected Saad from the game.

In a dramatic moment, Bieniewicz' wife, Kris Bieniewicz, held up a red card in court Friday, signalling the ejection. Saad expressed remorse.

He will be eligible for parole after eight years. His maximum punishment is 15 years in prison.