UPDATE: The Phillies and Nationals have released statements on behalf of Howard and Zimmerman.

"Ryan Howard has vigorously denied the allegations contained in tonight's airing of Al Jazeera's report titled 'The Dark Side.'  Ryan has spent his whole career with the Phillies and, during that entire time, has been an extremely well respected member of our team and an outstanding contributor to our community.  We will fully cooperate with any investigation conducted by Major League Baseball and will refer all further questions to them concerning the Al Jazeera report." 

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Although Peyton Manning was the headlining name mentioned in last night's report from Al Jazeera documenting a doping ring supplying professional athletes with performance-enhancing drugs, a few MLB players were also allegedly involved in the operation.

Philadelphia Phillies first baseman Ryan Howard, Washington Nationals infielder Ryan Zimmerman and Chicago Cubs catcher Taylor Teagarden were among the others said to be supplied with a human growth hormone banned in professional sports.

Here's the synopsis of the report from The Huffington Post:

"The report, 'The Dark Side,' is the result of a monthslong investigation in which Liam Collins, a British hurdler, went undercover in an attempt to expose the widespread nature of performance-enhancing drugs in global sports. As a cover story, Collins tells medical professionals tied to the trade of performance-enhancing drugs that he is hoping for one last shot at glory at the 2016 Olympics in Rio de Janeiro, Brazil."

Check out the full documentary here.

Collins managed to get in touch with Charlie Sly, who is a pharmacist based in Austin, Texas. Sly previously worked at the Indiana-based anti-aging clinic - the Guyer Institute - that was the focus of Al Jazeera's investigation. Sly said he supplied Howard and Zimmerman with a drug called Delta-2, which is a "hormone supplement that is steroidal in nature, but is not an anabolic steroid." The substance is banned by the MLB.

Sly explained Delta-2 is "designed to stay ahead of drug tests," meaning it's not detectable.

Zimmerman and Howard responded to Al Jazeera and denied their alleged use of PEDs. A scene in the documentary revealed Teagarden talking about his use of PEDs last year, but Al Jazeera did not mention his name beyond that in the report.

Manning, Zimmerman, Howard, Mike Tyson, Clay Matthews, Mike Neal, Julius Peppers, James Harrison, Dustin Keller and others were among those Sly unearthed in the report.

Stay tuned for updates on this developing story.