Don Samuel said Blaylock blacked out prior to the Atlanta-area collision in which Monica Murphy, 43, was killed, The Atlanta Journal-Constitution reported Wednesday.
Blaylock was seriously injured when he crossed into opposing traffic Friday and collided head-on with a vehicle driven by Frankie Murphy, police said. His wife, Monica Murphy, died later in a hospital.
Frankie Murphy sustained a broken ankle.
Samuel said it was not yet known if the cause of the blackout was "from his NBA career or something else."
He described Blaylock, who remains hospitalized, as "terribly upset about what happened."
Blaylock was charged Monday with second-degree vehicular homicide, driving with a suspended license and several traffic violations.
Neither alcohol nor drugs are believed to be factors in the collision, investigators say. Toxicology tests have not yet been completed.
Samuel said he hoped the incident "can be resolved by insurance companies, not criminal charges."