The son of former New York Mets star Bud Harrelson was sentenced to five years probation Monday for hindering the prosecution in the samurai sword slaying of a retired police officer.

Troy "T.J." Harrelson, 19, was the key witness in the trial of his one-time best friend Zachary Gibian for the 2005 murder of Gibian's stepfather, Scott Nager.

Harrelson could have been sentenced to 90 days in jail for helping Gibian dispose of evidence if he had not made a deal with prosecutors. Harrelson also was sentenced to 420 hours of community service.

"He provided truthful testimony and otherwise complied with the terms of the cooperation agreement," said Suffolk County Assistant District Attorney John Scott Prudenti.

Gibian, 20, of Hauppauge, was sentenced on Jan. 17 to 25 years to life in prison for second-degree murder in the death of Nager, 51, a retired New York City police officer.

Harrelson testified that he went to Gibian's home after his friend called him for a ride on the morning of the killing. But he recalled few details because of his admitted use of marijuana, cocaine and OxyContin.

A judge ordered Harrelson to enter an inpatient drug treatment program after the teenager pleaded guilty to one count of hindering prosecution on Jan. 9.

Bud Harrelson is a two-time All-Star shortstop who played for the Mets for 13 years in the 1960s and '70s and later managed the team in the '90s. He is co-owner of the Long Island Ducks minor league baseball team.

Gibian claimed Nager sexually abused him since age 15. Prosecutors said the allegations of sex abuse were "preposterous."