Mack Breed, a high school assistant coach in San Antonio, acknowledged that he directed two of his players to hit a referee during a game this month, the school’s principal said. In an internal school district statement, Robert Harris, the principal of John Jay High School, said that Breed had told him he directed the students to hit the referee Robert Watts because Watts had used racial slurs and had missed calls. Watts has denied using slurs. The players, Michael Moreno and Victor Rojas, have been suspended, and they appeared Wednesday at disciplinary hearings that were closed to the public.