A youth soccer coach went to the middle of a sports field in Windsor after a contentious match and pulled down his pants, exposing his buttocks to his opponents - a team of 14 and 15-year-old girls, authorities said today.

Several of the girls and their parents were offended by the action on Saturday and immediately called police, who plan to ask Sonoma County prosecutors to file misdemeanor indecent exposure charges against the coach from Petaluma, Windsor police Sgt. Steve Brown said.

The coach, who was not identified, was leading his team in an under-16 tournament game at Hiram Lewis Park. The contest had featured physical play and "heated arguments," Brown said in a written statement.

After the alleged gesture, police officers spoke to the coach, who denied exposing himself, Brown said. He said the coach had been suspended.