Earlier this week, NFL Commissioner Roger Goodell responded to a letter he and NFL Players Association chief DeMaurice Smith received from two congressmen calling for the NFL to adopt a "thorough testing program for HGH."

Goodell said in his reply dated June 13 that testing for HGH "is a critical element of an effective and credible drug testing program" and the league is insisting on "immediate implementation of HGH testing" in negotiations for a new collective bargaining agreement.

The NFL and NFLPA also discussed the policy before the union decertified March 11 and league owners imposed a lockout March 12.

Adolpho Birch, the NFL's vice president of law and labor policy, said in March that the league has pushed for HGH testing since 2008, but with the opportunity to re-cast terms of a labor deal, it has become a priority. The NFLPA had resisted it in the past because of HGH testing methods and the reliability of results.

Blood testing remains the most reliable means to detect the presence of HGH, and that has been the sticking point -- not both sides' desire for fair play, Birch said.

"In terms of the policy, we've always been in lockstep with the players," Birch said. "It's an important tool in deterring -- that's maybe the most important part -- and detecting those who are using (HGH). It helps the public understand what they are seeing is legitimate and that it's not the result of artificial means. It's equally important to players to know that someone hasn't gained an artificial advantage over them."

Whether or not such a provision makes it into the CBA, it's clear that deadlines are approaching. Training camps normally would open in about five weeks, and any lengthy delays in striking a deal will endanger them and the preseason. The first preseason game is at the Pro Football Hall of Fame inductions; the Bears and Rams are scheduled to play Aug. 7 in Canton, Ohio.

The Associated Press contributed to this report.