Speaking to Outside The Lines on Thursday night about the investigators, Sly said: "Those guys were great guys. Like, very good guys. Very professional."
Sly is the Indiana pharmacist at the center of the Al-Jazeera America documentary that aired Dec. 27. In it, the network reported that Manning's wife had received shipments of human growth hormone. Manning has denied the allegation, calling it "completely fabricated, complete trash, garbage." In the documentary, Sly -- caught on hidden camera -- named several professional athletes as possible dopers.
According to Brownsburg, Indiana, police, the two investigators went to the home of Sly's parents on Dec. 22 looking for him. Sly's sister, apparently alarmed, called 911 and said the men claimed to be law enforcement. Police responded, but the men provided identification and were invited into the family home. Sly was not there at the time. No arrests were made, and no incident report was filed.
Sly would not say when he spoke to the investigators.
Manning's lawyers launched the private probe shortly after Al-Jazeera America started contacting athletes who would be named in the documentary in December.
They hired investigators to identify, locate and interrogate Sly and sent a lawyer to examine the medical records of Manning and his wife, Ashley, at the Guyer Institute of Molecular Medicine in Indianapolis, according to Ari Fleischer, the former White House press secretary and current crisis-management consultant hired by the Denver Broncos quarterback.
Sly insisted again Thursday that he never provided drugs to any of the athletes mentioned in the documentary.
"I don't see how [Al-Jazeera] can say all this," he said. "There's no proof to any of this stuff."
In the documentary, Sly was caught on a hidden camera saying that he provided banned substances to several professional athletes and strongly suggested that an Indianapolis anti-aging clinic where he used to work provided HGH to Manning. Manning said the clinic sent prescription drugs to his wife for undisclosed reasons and denied ever using HGH or anything that was sent to her. On the day the documentary was broadcast Sly released a video denying everything he said to Al-Jazeera, reading a statement that he told Outside the Lines was vetted by Manning's attorneys.
When Outside the Lines first contacted Sly about the report in December, he said he would be able to speak only with the permission of his attorney and attorneys for Manning.
One of the more damning pieces of video from the documentary was a conversation between Sly and journeyman catcher Taylor Teagarden, who played eight games with the Chicago Cubs last season. In the video, Liam Collins, a former British hurdler who acted as an undercover reporter for Al-Jazeera America, is introduced to Teagarden at Sly's apartment. He asked Teagarden if he had taken the drug Delta 2, and Teagarden said he had. "And I was also taking peptides too," Teagarden said, referring to class of banned performance enhancers.
In the video, Sly said to Teagarden that he "put everything in that bag." Teagarden is heard to say, "Everything I need is in here?" Sly said, "Yes."
Asked about the exchange, Sly said Teagarden lied to Collins.
"He antagonized [Teagarden] into saying it," Sly said. "I can't blame Taylor for giving that guy some s---. Baseball's being unfair to [Teagarden] because they don't know the background."
Teagarden did not respond to numerous requests for comment over the past several weeks.
Investigators from Major League Baseball and the NFL have reached out to Sly through his attorney, Travis Cohron, who said: "we are fully cooperating and expect to meet with both sometime in the weeks ahead."
MLB is conducting a coordinated investigation with the U.S. Anti-Doping Agency The NFL says it is also investigating the allegations against Manning and other NFL players, including Mike Neal, Clay Matthews and James Harrison.
In the video, Sly was also recorded telling Collins that he provided to drugs to major leaguers Ryan Howard and Ryan Zimmerman. Asked why he named those athletes specifically, Sly declined to answer and said he had never met them.
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