The American football player injured by a dirty tackle during a May 6 game has filed a criminal complaint with the Metropolitan Police Department against two former coaches of a rival team, sources said Thursday.

The criminal complaint by Kwansei Gakuin University quarterback Kosei Okuno alleges former Nihon University head coach Masato Uchida and former assistant coach Tsutomu Inoue instructed one of their players to injure him.

The police were already investigating the matter based on a victim report previously filed by the injured player, but filing a criminal complaint indicates the victim is seeking punishment.

The criminal complaint was filed along with a petition signed by thousands of people seeking leniency over the criminal responsibility of Taisuke Miyagawa, the Nihon University linebacker who committed the flagrant illegal hit, citing the "social sanctions" he has faced.

Earlier this week, Uchida and Inoue received a lifetime ban from the ruling body for college football in the capital and surrounding area.

The Kantoh Collegiate Football Association ordered the heaviest possible punishment, after determining that the two ordered the foul play in the game in Tokyo.

Okuno was hit by Miyagawa from behind long after the quarterback released the ball and suffered injuries to his back and elsewhere.