The FBI revealed encrypted messages exchanged between the defendant and Okagbare.
Blessing Okagbare's hopes of being cleared of the doping allegations which led to her suspension during the Tokyo Olympics are gradually evaporating.
This follows a statement issued on Wednesday by the United States Department of Justice on its findings.
The statement revealed that a man linked with Okagbare has been charged to court for allegedly providing performance-enhancing drugs to athletes competing in last summer's Tokyo Olympics, including Nigeria's celebrated queen of the tracks.
Eric Lira, 41, of El Paso, is the first person to be charged under a new U.S. anti-doping law governing international sports competitions.
The U.S. Attorney's Office in Manhattan said Mr Lira distributed the drugs, including human growth hormone and erythropoietin, a blood-building hormone, "for the purpose of corrupting" the 2020 Games, which were held in 2021 because of the coronavirus pandemic.
Mr Lira also is accused of conspiring to violate drug misbranding and adulteration laws.
Before now, there have been no new updates from the Athletics Integrity Unit (AIU) since placing a provisional suspension on Okagbare for the supposed doping infractions.
Nigerians and the world at large woke up to shocking news of the suspension of Okagbare on the eve of the Women's 100m semi-final race at the Tokyo Olympics.
While Okagbare's compatriot, Grace Nwokocha went on to compete in one of the semi-final races but failed to make the final, it was a lesser concern for many compared to the devastating blow on the most celebrated Nigerian athlete in recent times.
The AIU in its first official statement on Okagbare who is Nigeria's 100m and 200m record holder said the athlete was provisionally suspended with immediate effect after a sample collected from the 33-year-old tested positive for Human Growth Hormone.
Growth hormone is a non-specified substance on the 2021 World Anti-Doping Agency (WADA) Prohibited List and a provisional suspension is mandatory following an adverse analytical finding for such substance under the World Athletics Anti-Doping Rules.
The AIU said it collected the sample from Okagbare during an out-of-competition test on July 19 and revealed the WADA-accredited laboratory that analysed the sample notified the AIU of the adverse analytical finding
The criminal complaint released Wednesday by the U.S. Department of Justice identifies Okagbare only as "athlete 1", but it includes details, including her performances in specific races, that make it clear she was one of Mr Lira's clients.
The Athletics Integrity Unit last year said Okagbare also had tested positive for a blood booster in Nigeria in June.
She was charged with failing to cooperate with the investigation after she disobeyed an order to produce "documents, records and electronic storage devices" in relation to the other charges, the AIU said at the time.
"When it's time to say anything, I will and it will be worth the wait," Okagbare tweeted last year.
The criminal complaint alleges that Mr Lira, a kinesiologist and naturopathic doctor, brought "misbranded" versions of the drugs to the United States from Central and South America before distributing them to athletes.
Federal authorities searched Okagbare's cellphone as she was returning to the United States from Tokyo and found she had frequently communicated with Mr Lira over an encrypted app, according to the complaint.
"Is it safe to take a test this morning?" Okagbare wrote in one message to Lira, according to the complaint.
"Remember I took it Wednesday and then yesterday again. I wasn't sure so I didn't take a test."
In another exchange, Okagbare wrote to Lira that she had just run the 100m in 10.63 seconds. "Eric my body feels so good," she wrote. "Whatever you did is working so well."
"You are doing your part and you will be ready to dominate," Mr Lira wrote to the athlete.
Mr Lira is the first defendant charged pursuant to the recently enacted Rodchenkov Act.
The Rodchenkov Act prohibits any person, other than an athlete, to knowingly carry into effect, attempt to carry into effect or conspire with any other person to carry into effect a scheme in commerce to influence by the use of a prohibited substance or prohibited method any major international sports competition.
FBI Assistant Director Michael J. Driscoll said: "Performance-enhancing substances deprive competitors of a level playing field. We allege Mr. Lira knew he was breaking the rules when he communicated with Olympians through an encrypted messaging app to hide his illegal activity. It's not winning if you take illegal substances - it's cheating, and Mr. Lira will now be forced to face the consequences of his alleged criminal actions."
The United States Department for Justice maintains that the accusations and the defendant are presumed innocent unless and until proven guilty.