The FBI has launched an investigation into the death of Jim Irsay, the 65-year-old owner of the Indianapolis Colts NFL team who struggled with addiction and died in May at a Beverly Hills hotel.
The probe, first reported by The Washington Post, is said to include a well-known California-based doctor who allegedly provided Irsay with opioid pills and ketamine injections in his final months.
The use of either to treat patients with a history of addiction is controversial.
Ketamine is an anesthetic used in depression therapy but can itself be addictive.
An overdose caused the death of "Friends" actor Matthew Perry in 2023.
A spokesman for the Colts on Friday told AFP the club was "aware of the investigation" into Irsay's death but had not been contacted by the FBI or been served with any subpoenas.
The doctor, Harry Haroutunian, did not respond to AFP's request for comment.
An FBI spokeswoman could neither confirm nor deny the existence of an investigation due to long-standing FBI policy.
Irsay, a larger-than-life billionaire who inherited the Colts from his father, Robert Irsay, and oversaw the franchise for decades, was found dead in the swanky Beverly Hills Hotel last May.
A death certificate signed by Haroutunian said the immediate cause of death was cardiac arrest, with acute pneumonia as a contributing factor.
No autopsy was performed.
Irsay had spoken publicly about his lifelong struggles with alcohol and substance abuse.
He said he had kicked his addictions in 2002, but he suffered a high-profile relapse in 2014 and was suspended for six games by the NFL.
Irsay and his family set up a recovery charity called Kicking the Stigma in 2022.
But according to the Post, Irsay slipped back into substance abuse the next year and suffered at least three overdoses that were kept quiet by aides prior to his death.
Police responding to the scene of Irsay's death were told he had been suffering chronic health issues, and medical officials concluded no autopsy was necessary, the Post reported.
His family also did not request an autopsy, and the club's statement simply said Irsay had died "peacefully in his sleep."
An avid collector who spent $100 million on music, sports, and other pop culture memorabilia and also enjoyed competitive powerlifting, Irsay steered the Colts to a Super Bowl win in 2007.
The franchise is now co-owned by his three daughters, including Carlie Irsay-Gordon, who is the Colts' CEO.