The head football coach at Northeast High School was arrested early Tuesday morning on charges that he beat his 17-year-old nephew with a crutch in the middle of the night.

James Cotham, 50, was taken into custody at his Pasadena home around midnight after police were called about a domestic dispute. He was charged with assault and second-degree child abuse by a custodian, according to court records.

The impact on the Northeast football program, which starts practice early next month, was not immediately clear. Mr. Cotham has coached in county schools for 25 years, and has been the Eagles' head coach for the past seven. Last...