New York light heavyweight James Butler, who fought under the nom-de-guerre “The Harlem Hammer,” pleaded guilty Monday to voluntary manslaughter and arson in the 2004 death of freelance sports writer Sam Kellerman.

Butler will be sentenced to 29 years and four months in prison by Superior Court Judge Michael Pastor on April 5, according to Deputy Public Defender Jack Keenan, who was handling Butler’s defense.

The 32-year-old entered his plea as jury selection was set to begin in his trial for the killing of Kellerman, who was the brother of Max Kellerman, a familiar face on the boxing scene via ESPN, Fox, and now HBO.

“I think it's a fair resolution of the case,” Attorney Keenan said. “He's always been sorry for what he did, and in the end he thought of Sam Kellerman as a friend.”

He and Butler were friends for many years and the boxer had been staying at Kellerman's apartment since late September.

Kellerman's body was found in his Hollywood apartment on Oct. 17, 2004. He had been bludgeoned around the head about 30 times while sitting at his desktop computer, police said. A hammer, of all things, was found near Kellerman's body, his car was missing, and his apartment was set on fire.

Butler had a pro record of 20-5. He is also a well known head case who shot to notoriety when he sucker-punched opponent Richard Grant in New York on November 2001 after losing a decision during a charity bout for police and fireman who survived 9/11.

He did time in Rikers Island for that offense. Butler has been in custody since his arrest three days after the Kellerman killing.