TAMPA — A fight that culminated in a deadly shooting Tuesday morning outside a North Tampa Whole Foods Market could be a case of self-defense, authorities said.

The altercation in a parking lot behind the store involved Deshaun Gregory, 31, and David Saunders, 37, a former arena football player who investigators say is the personal trainer of Gregory's girlfriend.

Gregory was shot in the head and killed. Saunders was questioned and then released while the investigation continued.

Saunders, of Tampa, describes himself on a LinkedIn profile as a self-employed personal trainer and a coach with the Tampa Bay Youth Football League. He has played for the New Jersey Red Dogs, New Jersey Gladiators, Grand Rapids Rampage, Columbus Destroyers and Tampa Bay Storm arena football teams.

The Sheriff's Office released the following account:

Just before 10:30 a.m., the Sheriff's Office got a 911 call about a fight between two men behind the store at 15524 N Dale Mabry Highway.

When deputies arrived, they found a dead man in the parking lot next to a white sport utility vehicle owned by Saunders.

The man, later identified as Gregory, of Tampa, was angry with Saunders, the Sheriff's Office said, and had driven to the location with his girlfriend Tuesday morning to confront him.

The men fought and Gregory pulled an 8-inch kitchen knife on Saunders. Saunders shot him in the head, investigators said.

Homicide detectives were still investigating, and the Hills-borough State Attorney's Office will make a final determination on whether Saunders will face charges or whether the shooting was justified.

The identity of the victim's girlfriend was not being released, the Sheriff's Office said, because she is considered a witness.

Authorities said they believe the location of the shooting was randomly chosen, and that the market did not play a role in it.

Staff writers Aimee Alexander and Dan Sullivan and news researcher John Martin contributed to this report.