LOS ANGELES » A former professional boxer convicted in the 1987 killing of his ex-manager has been sentenced to 11 years in prison.

Fifty-one-year-old Exum Speight was sentenced Tuesday in Los Angeles after pleading no contest to voluntary manslaughter.

Authorities say Speight stabbed, strangled and beat 30-year-old Douglas Stumler, who was found dead in his West LA apartment.

Stumler worked for the Los Angeles County Housing Authority and worked on the side as a boxing manager.

He represented Speight for two years before they had a falling out.

In 1996, Speight lost a bout to Wladimir Klitschko, who’s currently the world heavyweight champion. Speight retired with a 9-39 record.

Authorities say DNA linked Speight to Stumler’s killing nearly a quarter-century after the crime.