Blain Padgett's body was found inside his home after he failed to show up for a Friday morning workout on March 2.
The Harris County Medical Examiner's Office concluded in June that Padgett, 21, died due to toxic effects of carfentanil, an analog of the synthetic opioid analgesic fentanyl.
#BREAKING: Police say Rice Football star #BlainPadgett’s death is now a homicide case. EXCLUSIVE THURSDAY NIGHT AT 10 in #ChauncyGloverReports For the first time, Blain’s parents are talking about their son’s death and the one pill that killed him. #abc13 pic.twitter.com/6BgZrzoYVG— Chauncy Glover (@ChauncyOnTV) October 3, 2018
RELATED: Blain Padgett, Rice Owls football star, died of effects from synthetic opioid, coroner rules
Padgett's father, Mical, said in a statement over the summer that his family wants to know how his son got a hold of the substance:
"The family is very devastated by the news and how it came out of the blue. The way we heard about it is very disappointing. We would like to know how Blain got his hands on this drug that seems very difficult to get. That's our main question. How did he get it and why did he take it? Sadly, nothing we find out will bring Blain back, which is what we really want."
News of Padgett's cause of death rocked Rice University, in addition to Padgett's former coach, David Baliff.
"I don't know if it makes it harder, but it opens it again," Bailiff said. "It makes you evaluate again as a man is there something else you could've done? Is there some other outreach that we could've lead to?"
READ MORE: Rice Owls football star Blain Padgett remembered
Dr. Richard Pesikoff, a Baylor College of Medicine employee, said carfentanil is a dangerous opioid that was designed to be an elephant tranquilizer.
It's 10,000 times more potent than morphine, and 100 times more potent than fentanyl.
Dr. Pesikoff said carfentanil is deadly because it causes the brain to suppress breathing.
RELATED: Rice Owls football star Blain Padgett dies
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