The NFL Player's Association has confounded the NFL and science experts in recent weeks by debating the validity of an HGH test that has been widely stamped for a approval by independent scientists, leaving some of those involved in the meetings to suggest that union politics are obstructing the process of drug testing. On Friday, owners of all 32 NFL teams received notice from the league that the HGH test would not be in place for the start of the regular season, though that was the previously agreed upon goal of the NFL and the NFLPA.

In a letter to NFLPA lawyers obtained by SI.com, NFL lead counsel Jeffrey Pash wrote that "we have now almost certainly lost the opportunity to implement this testing by the start of the regular season, and would therefore request that you let us know at the earliest possible time whether there are any remaining issues."

Gerry Baumann, professor emeritus in medicine-endocrinology at the Northwestern University Feinberg School of Medicine and perhaps the world's foremost authority on human growth hormone, thought that any lingering scientific issues were answered in the NFL and NFLPA's meeting last month at World Anti-Doping Agency headquarters in Montreal, which he attended as an independent expert. "To my knowledge, in the scientific community there's very little disagreement about the [HGH] test," Baumann says. "From my perspective, it appears to be quite reliable and quite conservative in terms of it errs on the side of avoiding false positives."

The NFL and the Player's Union agreed in July to begin blood testing for HGH as part of the new collective bargaining agreement, but in recent weeks the union has taken a defensive stance regarding the testing. Until an agreement is reached, the NFL's usual drug testing will proceed without an HGH test.

Baumann, who agreed to speak about the meeting at WADA headquarters in general terms, has been studying and working with human growth hormone for 30 years. He is an expert in the use of growth hormone treatment in adults and has been at the forefront of a number of major human growth hormone-related breakthroughs, among them the first sequencing of the gene that codes for the body's growth hormone receptors. And he has no vested interest in either side. Baumann walked away from the Montreal meeting feeling that, at least among the scientists in the room, there were no outstanding issues about the validity of the HGH blood test. Baumann says that he was asked "very few questions" during the meeting and that "the Player's Association side didn't raise any questions."

David Howman, director general of WADA, got the same impression. "There was no suggestion of challenge to the science," says Howman. "There weren't any high degree science questions that came up with our scientists." Which is why Howman told The New York Times that the union's science team had "accepted the test's validity." That interpretation of the meeting earned him a public rebuke from union spokesman George Atallah who said that Howman "should not be so arrogant and presumptuous to speak on our behalf or on the behalf of anybody from our team." (View the WADA presentation here.)

The scientific team from the union included two scientists from Aegis labs in Nashville and Paul Scott, a lawyer with an undergraduate degree in chemistry and biology and head of Scott Analytics, an anti-doping services firm. When contacted, Scott was not allowed by the NFLPA's legal team to discuss the meeting. Maurice Suh, an attorney representing the NFLPA in the discussions, did not return a call seeking comment.

A conspicuous absence from the union's team at the meeting was NFLPA president DeMaurice Smith. According to three people who attended the meeting, Smith canceled the day before, to the dismay of commissioner Roger Goodell and NFL executives. (Atallah could not be reached by phone and another union spokesman did not return a message seeking comment.)

According to three people who are familiar with the HGH-testing discussions between the NFL and NFLPA, Smith has been under pressure to show some resistance on HGH testing because perception among some players is that the union hastily agreed to it in collective bargaining. As Steelers safety and player representative Ryan Clark put it: "I think people wanted to get a deal done so badly that it was overlooked ... In that sense, players kind of got screwed, for lack of a better word."