Stuart "Mooch" Mouchantaf, 26, has been charged with three federal counts of conspiring to distribute and possessing with intent to distribute a powerful opioid analogue.
Blain was a Rice University football star who died on March 2, 2018. His body was found in his bedroom by fellow players after he failed to show up for a morning workout.
The Harris County Medical Examiner's Office concluded in June 2018 that Blain, 21, died in his sleep due to toxic effects of carfentanil, an analogue of the synthetic opioid analgesic fentanyl.
Mouchantaf is accused of giving the deadly pill to Blain. Authorities say that Mouchantaf possessed the drug with the intent to distribute it on the Rice University campus the day before Blain's body was found.
Friday, a judge ruled Mouchantaf must wear a GPS monitor as a condition of his bond. He will likely process out of a Conroe holding center later Friday night.
Mouchantaf's mother was seen crying in the courtroom as she watched the proceedings. His next hearing is scheduled for Wednesday.
EXCLUSIVE INTERVIEW: Grieving mother of Rice Owls star speaks on son's drug death
Mouchantaf had already been charged with delivery of a controlled substance resulting in death, a 2nd-degree felony that carries a penalty of five to 99 years or life in prison.
He was re-arrested Thursday by authorities as he stepped off the elevator at Harris County District Court.
Mouchantaf is expected to make his initial appearance before a U.S. magistrate judge on these federal charges on Friday.
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On Thursday, Rice University provided this statement following Mouchantaf's arrest:
"Out of respect for the legal process, the university does not have a comment on today's federal arrest or on any possible details of the case."
Blain's father, Mical Padgett, said he believes his son had no idea the pills he took were laced with carfentanil.
"He knew that he should not have been taking it, but he did so," Mical said. "I know if he was here, he would say, 'Hey, I take responsibility for this.'"
According to court papers filed by prosecutors, Houston police investigators found that Blain bought pills from Mouchantaf, believing that they were Hydrocodone. It turns out the pills were laced with carfentanil.
"Blain knew about choices like drinking and driving, but I think that this is something that is fairly new, at least it's new to us, that you don't take anything from anyone unless a doctor has prescribed it for you, period," said Blain's mother, Wyndi Padgett.
A lethal amount of carfentanil is so small, it's invisible to the human eye. It was originally made as an elephant tranquilizer.
Carfentanil is 10,000 times more potent than morphine, and 100 times more potent than fentanyl.
Doctors say it's deadly because it causes the brain to suppress breathing.
"Buyers need to understand that when they buy these pills on the streets instead of pharmacies, they are literally playing Russian Roulette," said Assistant District Attorney Paul Fortenberry. "These pills look like the real deal, but they, in fact, are far more dangerous than even cocaine or heroin and are far less expensive."
WATCH: What are Fentanyl and carfentanil?
According to the roster on the Rice website, Mouchantaf is from Katy.
He graduated from Cinco Ranch High School, where he was a three-year starter for the Cougars. He also participated in Cinco Ranch's Peer Assistance and Leadership, or PALS, program.
He signed with Rice University in 2012 after playing at Blinn Junior College.
Last October when Mouchantaf was originally charged, his bond was set at $250,000 because he was considered a flight risk.
Police said at the time Mouchantaf bought a one-way ticket to Lebanon and has family there. He was ordered to surrender his passport and wear an ankle monitor.
EXCLUSIVE: Only #abc13 cameras rolling as Former Rice University football player Stuart Mouchantaf went before a judge. The 25yo charged with delivery of a controlled substance. Police say he gave #BlainPadgett a hydrocodone laced with carfentanil. Blain took the pill and died. pic.twitter.com/GU2IAtFKxn— Chauncy Glover (@ChauncyOnTV) October 5, 2018
RELATED: Blain Padgett, Rice Owls football star, died of effects from synthetic opioid, coroner rules
News of Blain's cause of death rocked Rice University, in addition to Blain's former coach, David Bailiff.
"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
After news of the arrest, Blain's father issued the following statement to Eyewitness News, referencing his son's death in March 2018:
"On March 1 of this year my son, Blain Padgett, made an unfortunate decision to buy what he thought was a pain pill from someone he trusted. That pill contained carfentanil, a highly toxic drug not meant for human consumption. Blain always took responsibility for the decisions he made and never made excuses. So I'm here to speak for him. He did make a bad decision and it cost him his life.
I expect these individuals responsible for making, distributing and selling this poison to take responsibility and to also pay for this crime.
I want to thank HPD for their hard work and, especially Detective Mike Miller, for seeing this investigation through and arresting Stuart Mouchantaf, who admitted to selling this deadly pill to Blain.
The Padgett family is not about drama, but we want other mothers, fathers, brothers, sisters and friends to learn from our tragedy. We don't want another family to endure the pain we're enduring right now."
Blain's family spoke to Eyewitness News about the last conversation they had with their son who injured his shoulder in fall 2017 and required surgery, ending his season.
They said he was determined to get back on the field. They spoke with him again on March 1.
"We had spoken on the phone 45 minutes to an hour," Mical said.
"That night was different. Blain was so excited about tomorrow. He had just been released from his surgery," Wyndi said.
After finding out how their son died, the Padgetts say they decided to share their story because they wanted to warn other families.
"Don't go a day without telling your kids and your parents, and your brothers, sisters that you love them, because you never know," Wyndi said.
ONE LITTLE PILL: Parents sound alarm after Rice football star's opioid death
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