Ray Lewis III -- the son of NFL legend Ray Lewis -- died from a lethal mix of drugs ... according to an autopsy report obtained by TMZ Sports.
In the medical examiner's documents, officials say fentanyl, cocaine and methamphetamine intoxication was what led to the former football player's son's passing.
They ruled the manner of death as accidental.
According to the toxicology report, Lewis III additionally had alcohol and alprazolam -- the drug found in brands like Xanax -- in his system at the time of his death.