NASHVILLE, Tenn. — An associate said today that the wife of ex-NFL quarterback Steve McNair didn’t know about Sahel Kazemi before the 20-year-old woman was found dead alongside her husband on the Fourth of July.

McNair, 36, was shot four times in what the medical examiner has said is likely a murder-suicide, though police haven’t confirmed that Kazemi was responsible.

Mike Mu, who has worked with McNair’s charitable foundation for years, said Mechelle McNair “didn’t know who this girl is.”

Mechelle McNair, who has not spoken publicly since the shooting, has been described by people close to her as being very upset and distraught. Agent Bus Cook said McNair’s wife was “in and out” of it in the hours after the shooting.

Kazemi’s family told reporters that the woman was so confident McNair was divorcing his wife of 12 years that she was preparing to sell her furniture and move in with the former quarterback.

Mu is handling media inquiries for Thursday night’s memorial service in Nashville. A funeral service will be held Saturday in Mississippi.

The close friend who reported McNair’s death to 911 defended his friend since their days playing football at Alcorn State to The Tennessean. Robert Gaddy, who did not immediately return a text message to his cell phone from The Associated Press today, said the the McNairs’ Nashville home was on the market because they were looking for a new house.

“People need to quit talking about what they don’t know. Mac never said anything to me about he was going to get a divorce, and ever since this has all happened everybody is trying to paint a certain picture and they need to talk about what they know,” Gaddy told the newspaper.

The four-time Pro Bowl quarterback was being remembered today at the stadium where he played much of his career. The Tennessee Titans opened LP Field for fans to watch video highlights of McNair’s 13-year NFL career, look at photos of the quarterback and had a book for them to write messages that will be given to the family.

The McNairs married in 1997, and Mechelle is the mother of two of his four sons. She met McNair while both were students at Alcorn State, though she also studied nursing in Nashville and became a nurse while he played for the Titans.

Mechelle McNair tended his numerous injuries at home, changing bandages and even helping with intravenous fluids in 2001 when her husband needed I.V. antibiotics for an infection that developed after shoulder surgery.

Tennessee’s state medical examiner said Tuesday that investigators have been hesitant to conclude that McNair’s girlfriend killed the NFL star and herself because she didn’t appear to have a motive, but that murder-suicide is the most likely scenario.

After the couple was discovered shot to death on Saturday, police were quick to label McNair’s death a homicide. He had been shot twice in the head and twice in the chest, whileKazemi was dead from a single gunshot to the head. Under her body was a gun she had purchased less than two days before the killings.

Investigators were waiting on ballistics tests on the weapon before issuing a ruling on Kazemi’s death, which medical examiner Bruce Levy said could come in the next few days. Kazemi’s gun purchase, which was revealed on Monday, is a strong indication that she was responsible, he said.

“If we had known on Sunday about the gun I think we would have been very comfortable in ruling murder-suicide,” he said. “I’ll be very surprised now if they rule it isn’t.”

Levy said an apparent lack of motive by Kazemi has made investigators careful about exploring every possibility, including the unlikely scenario that a third party could have staged the scene.

Their relationship lacked typical indicators of trouble — such as concerned family members or police reports and protection orders.

“The thing we always hear is, ‘We should have seen this coming,’” he said.

But Kazemi’s family has said she was very happy.