Three Wisconsin basketball officials file a complaint on Mike McCarthy for using "unsportsmanlike language" toward them after his stepson's team lost. (0:34)

Three referees in Wisconsin have filed a formal complaint against former Green Bay Packers coach Mike McCarthy after he was involved in an incident during his stepson's high school basketball game Tuesday.

Video appears to show McCarthy follow the referees as they made their way out of the gym after the game, a one-point loss by Notre Dame Academy, for which McCarthy's stepson plays, to Pulaski High School. District officials confirmed to Fox 11 in Green Bay that the man in the video was McCarthy and said he directed "unsportsmanlike language" at the referees.

"This parent chose to follow the officials and berate them, which is clearly unacceptable," Janel Batten, Pulaski's athletic director, told Fox 11. "Some things were said, some language was used that we don't want in our gym, unsportsmanlike language."

The complaint was submitted Wednesday to the Wisconsin Interscholastic Athletic Association.

Notre Dame Academy athletic director Steph Mathu said in a statement Thursday that the "parent involved" had apologized to a school administrator, adding that "we appreciate his outreach."

McCarthy, 55, has said he plans to coach again in the NFL but will sit out the 2019 season. He went 135-85-2 in 12-plus years with the Packers but was fired with four games left in the 2018 season.