DETROIT -- A high school hockey coach honored as one of the best in Michigan will plead guilty to sexually assaulting a teen boy and be sentenced to more than 17 years in prison, a prosecutor said Tuesday.

Separately, Robert Bopp will go to federal court to plead guilty to a crime related to the case, lawyers said.

Bopp, 53, was accused of paying at least $150 to have oral sex with a boy in 2007 and 2008 when the victim was 14 and 15. He will plead guilty next year to first-degree criminal sexual conduct in a deal that carries a minimum sentence of about 17 1/2 years, prosecutor Lora Weingarden told a Wayne County judge.

Bopp was fired as coach at Grosse Pointe South High School after he was charged in June. He led the Blue Devils to a state championship game in 2007 and is a member of the hall of fame for Michigan prep hockey coaches.

At a court hearing in July, the alleged victim said he agreed to be paid to have oral sex with Bopp because he needed money for drugs. He said he was introduced to Bopp -- he knew him as "Justin" -- through an acquaintance.

There was no dispute the sex acts occurred. Andreoff had argued there was no evidence that Bopp knew the boy was under 17. A judge, however, said that was no defense.

Bopp is expected to plead guilty in federal court before he appears in state court, Weingarden said. The move is tactical, since a conviction in state court could lead to a longer federal sentence.

The federal charges are not yet filed. The FBI has said it searched Bopp's home in Taylor and seized photos of him having sex with minors. Officials at the U.S. attorney's office did not immediately return a call Tuesday about the apparent deal.

"The charges haven't been finalized. Hopefully by the end of the week this will be resolved," defense attorney Christopher Andreoff told The Associated Press.