MONROE, N.J. (AP) — A high school football coach criticized a referee who refused to officiate a game after members of the opposing team knelt during the national anthem.

Referees Ernie Lunardelli and his son, Anthony, said they told officials from Colts Neck and Monroe high schools before Friday night’s game they would walk off the field if any players protested. They said they respect players’ right to protest but believe such acts are disrespectful.

Colts Neck Coach Darian Barnes told NJ.com that Ernie Lunardelli yelled at Monroe players after some knelt, and he had to be pulled off the field, accusations Lunardelli denies. Lunardelli said he only stopped on his way off the field after a coach from Monroe yelled at him.

“One of the coaches said something and it kind of irked me, and I just turned around and I was looking to see who it was,” Lunardelli said. “Nobody pulled me; I walked off.”

Barnes agrees referees and players should be able to express their views but says Lunardelli was “a coward” to yell at the teenage players.

“It wasn’t difficult to watch those kids kneel and it wasn’t difficult to watch him leave the game because of it,” Barnes said. “His anger was difficult. His anger, the way he yelled, the look on his face — it bothered ... me.”

Barnes also said he was told before the game by the head referee that the crew had asked the Monroe players who might kneel to stay in the locker room for the anthem to avoid any problems.

The trend of kneeling during the national anthem started in the NFL, where some players kneel to protest social injustices, particularly against African-Americans.