DENVER -- The NFL says it is conducting a comprehensive review of allegations that Broncos quarterback Peyton Manning had human growth hormone delivered to his house.

A source told FOX Sports' Mike Garafolo recently the NFL already has requested an interview with Manning (as well as the other players named in the report, including the Packers' Julius Peppers and Mike Neal) to ask their own questions about the allegations. But the source said that interview won't occur until after this postseason is completed, if at all. There's no timetable to complete the investigation.

League spokesman Brian McCarthy says the inquiry, which began weeks ago, involves reviews of records, interviews and coordination with other agencies.

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Al Jazeera reported last month that an intern at an Indianapolis anti-aging clinic was secretly recorded suggesting that Manning's wife received deliveries of HGH, which is banned by the league. Manning, then with the Colts, was rehabbing from shoulder surgeries.

The intern, Charles Sly, has since recanted his story.

Manning angrily denied using performance-enhancing substances and called the report ''complete garbage.''

The Associated Press contributed to this report.