Andre Direll's uncle Leon Lawson could face a maximum sentence of 25 years in prison if he is sound guilty of first degree assault.
The trainer punched an unawares Jose Uzcategui after the Venezuelan fought his nephew in a boxing match in Maryland on Saturday.
Uzcategui was disqualified after the referee adjudged he had hit his opponent after the eighth-round bell.
But Lawson took things into his own hands as his nephew was keeled over and being seen to by doctors in the ring. He unexpectedly clocked Uzcategui in the chin in shocking scenes.