The death of former Dallas Cowboys running back Marion Barber has been ruled accidental.
The report from the Collin County Medical Examiner's office, released Monday, listed Barber's cause of death as heat stroke.
Barber, 38, was found unresponsive inside his Frisco apartment on June 1 by police officers responding to a welfare check.
It's not immediately clear what Barber had been doing in the moments leading up to his death.
Barber's friend and attorney, Billy Clark, told NBC 5 last month that Barber was still in tip-top shape and had been training to become a boxer.
Barber was drafted by the Dallas Cowboys in the fourth round in 2005 and spent six seasons in North Texas where his hard-hitting, punishing style of running earned him the nickname "Marion the Barbarian."
After leaving Dallas, Barber would spend a year with the Chicago Bears before retiring from professional football and returning to North Texas.
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Throughout his NFL career, Barber rushed for 4,780 yards on 1,156 attempts, an average of 4.1 yards per attempt, and scored 53 touchdowns on the ground. As a receiver, he caught 179 passes for 1,330 yards with six TDs.
Barber is the older brother of former Houston Texans safety Dominique Barber and former Minnesota Golden Gophers linebacker Thomas Barber. They are the sons of former NFL player Marion Barber Jr.
Barber was also known for his humanitarian efforts, working with his foundation and giving back to his community.