Here's how it would work under the proposed agreement. Say a player tests positive for HGH or performance-enhancing drugs (PEDs) and is suspended by Goodell. The NFL made what it considers a major concession in agreeing to let third-party arbitrators hear his appeal.
But what if federal authorities bust a player for involvement in a PED ring or other violations of the law? The league wants the commissioner's office to retain its long-held authority over appeals in such cases rather than having arbitrators decide them.
Each side blames the other for the impasse, of course.
According to Adolpho Birch, the NFL's senior vice president of labor policy and government affairs, the NFLPA has "buyer's remorse" and is trying to "renegotiate" a deal it already signed off on.
"The union knows that HGH testing is the right thing to do for our game, for its membership and for the millions of people who look to the NFL and NFL players to set the example for fair and exciting play," Birch said in a statement. "It is time for the NFLPA to stop the delay tactics, to move forward for the good of the game and players, and stop focusing on protecting people that break the law."
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Atallah countered that the league is dragging its feet. For almost a month, the NFL has had the signed letter from the union proposing the population study. But the league is more "interested in power" than getting HGH testing resolved.
"The 'buyer's remorse' issue is simply meant to divide our members," Atallah said.
Even Congress is getting fed up. Rep. Elijah Cummings (D-Md.), ranking Democrat on the House Oversight and Government Reform Committee, has publicly threatened intervention and has rebuked the union.
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"After two years of negotiations, the NFLPA is now holding HGH testing hostage because of matters wholly unrelated to testing," said Cummings in a statement. "Continuing to block HGH testing in this way essentially will force Congress to intervene, which nobody wants."
Although the NFL has escaped Major League Baseball's PED scandals, one thing MLB can boast is that it tests for human growth hormone.
"We are the only North American professional sports league currently testing for HGH," said MLB spokesman Michael Teevan.
MLB began blood-testing minor league players for HGH in July 2010 and expanded the program to big leaguers during spring training last year. In the current 2013 season, all MLB players are subject to random, unannounced blood tests for the substance.
Former New York Mets player Mike Jacobs became the first pro athlete in the U.S. to test positive for HGH while playing for a minor league affiliate of the Colorado Rockies in 2011. Blood testing for HGH was first used at the 2004 Summer Olympics Games, according to the World Anti-Doping Agency (WADA).
The other major professional leagues want to test their players for HGH, but they also trail MLB.
David Stern, outgoing commissioner of the National Basketball Association, has been a strong supporter of testing, according to league spokesman Tim Frank. It has nothing in place yet, however.
Similarly, the National Hockey League and its players' association are "contemplating" HGH testing under the 10-year collective bargaining agreement signed this year, but there's nothing definite, according to league spokesman Jamey Horan.
So what's behind the holdup to HGH testing in the NFL?
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