Ex-NFL quarterback Steve McNair's mistress bought the gun she used to kill him from a convicted murderer whose fiancee was afraid to have it in the house, authorities said yesterday.

Adrian J. Gilliam Jr., 33, of La Vergne, Tenn., was charged with being a convicted felon in possession of a firearm. He admitted selling a 9 mm Bryco/Jennings to Sahel Kazemi for $100, according to court documents.

Kazemi, 20, shot McNair to death at his condo July 4 before killing herself in Nashville, Tenn. Authorities say she met Gilliam while she was trying to sell her a car and told him she was looking to buy a gun.

A criminal complaint says Gilliam — who was convicted in 1993 in Florida for murder and attempted armed robbery — told police he sold the gun to Kazemi, whom he identified from a police photo.

Detectives traced the gun to its 2002 sale at a pawn shop. Gilliam eventually bought it from someone for $100 about a year or year and a half ago. Investigators said he told them he bought it for protection after his home was burglarized, and police reports show a burglary around that time.

Nashville Police Chief Ronal Serpas said at a news conference yesterday that Gilliam decided to sell the gun because his wife was afraid to have it in their house.

Federal Public Defender Hugh Mundy said Gilliam is not married but is engaged to a woman with whom he has a 2-year-old daughter.

Gilliam has been out of jail for seven years and has had no other trouble with the law in that time, Mundy said.

"No one denies this is a tragedy," he said. "Steve McNair was one of Nashville's heroes. A lot of lives have already been ruined. But Mr. Gilliam is a decent, hardworking family man and there's no reason to ruin his life, too."

DOLPHINS

MARC ANTHONY TO TEAM UP WITH MIAMI

Marc Anthony is the latest celebrity musician to join forces with the Miami Dolphins.

The team scheduled a news conference to be held Tuesday in New York for a "major corporate announcement" with Anthony.

It was unclear whether Anthony will become a minority owner. That's what happened last month when singer Gloria Estefan and her husband, producer Emilio Estefan, bought a small stake in the team.

New Dolphins owner Stephen Ross also began a partnership in May with Jimmy Buffett's Margaritaville enterprise, which includes Land Shark Lager.

EAGLES

CB ACQUITTED OF BURGLARY CHARGES

Philadelphia cornerback Jack Ikegwuonu has been acquitted of burglary charges in Illinois.

A DeKalb County judge acquitted Ikegwuonu yesterday of residential burglary and criminal trespassing.

Ikegwuonu and his twin brother, Bill, were arrested in November 2006. They were accused of trying to steal a video game system from an apartment in DeKalb.

Jack Ikegwuonu was playing for Wisconsin when he was arrested. He was drafted by the Eagles last year but didn't play all season because of reconstructive knee surgery.