One shaky source is making Peyton Manning’s life miserable.

The Al-Jazeera news network ran a report on the shady network of sports doping. Just past the 40-minute mark, the report — much of it undercover taping — shows a pharmacist claiming that he sent human growth hormone (HGH) to Manning in 2011, and that he addressed the packages to the Bronco QB’s wife to help hide the purchases.

The revelation was explosive and has led to angry denials by Manning himself. It has also touched off a huge debate about whether the 18-season veteran, one of the NFL’s most reliable role models, is instead a cheater.

My concern, as a journalism professor, is the unreliable nature of the Manning info. The Al-Jazeera report relies on one source — Charlie Sly — for the information, and Sly himself recants at about the 47:35 mark.

The report presents no receipts or correspondence, no second source acknowledging Manning’s involvement. Just one interview, with the source later presenting himself as flaky.

The NFL Sunday/social media blowup over this has exploded past this troubling detail, as can be expected. It is obvious that the majority of those commenting have not viewed the report itself, to see the thin ice supporting the information.

I’m not judging whether Manning used HGH. I’m wondering why a respected news organization released a news report before it was ready.

Al-Jazeera or another organization might come up with a second source (a more reliable source, I hope). At that point, the ethical question becomes, Why not wait? Why run the story before it’s ready? And responsible journalism ethical standards dictate that a story is not ready until you have a second source.

Does Manning have a case for libel? As a public figure, probably not — even though Sly’s recanting brings the information a little closer to “actual malice,” the definition of which includes “reckless disregard of whether (the information) was false or not.”

Plus, within the definition of public figure status, Manning has the means to dispute the report within the media, and he is obviously using them.

Can Sly, who is more of a private citizen than Manning, sue for invasion of privacy? It’s an interesting intersection between two conflicting rules. On the one hand, Al-Jazeera is safe on the issue of consent; Texas is a “one-party state,” meaning only one person needs to be aware of the taping.

On the other hand, previous Supreme Court decisions do not 100 percent permit deception in taping a private citizen or business, and the Al-Jazeera report was based on an athlete, Liam Collins, deceptively claiming he was looking for shortcuts, legal or not, to restart his athletic career. I don’t know whether this conflict has been resolved within the courts.

But from an ethical perspective, Al-Jazeera is on much shakier ground, and needed more corroboration before releasing information that so damaged one athlete’s reputation.

To contrast, I remember a mini-storm this summer, surrounding the death of legendary SEC/NFL quarterback Ken Stabler. A report on Stabler’s death July 8 was released on the Tuscaloosa News web site and then taken down quickly, but not before it was cited and the news spread nationwide.

The sports writer generating the report, Aaron Suttles, had a good source informing him that Stabler had died, but was awaiting a second one to confirm it before posting the article he had ready.  Due to miscommunication, a digital staff member posted the report.

Anyone who knows Suttles recalls his mortification and regret — not because the story was not accurate (obviously it was, as would be demonstrated), but because it was not “ready” in terms of sourcing, even as subsequent events confirmed the information’s reliability.

If only Al-Jazeera were so careful on a story that involves an active SEC/NFL quarterback, who now must deal with the public fallout of a shakily-sourced report. Manning, the audience, and the journalism profession deserve better.