Three star linebackers heard the NFL’s message loud and clear.

James Harrison of the Pittsburgh Steelers and Clay Matthews and Julius Peppers of the Green Bay Packers have agreed to meet with NFL investigators regarding performance-enhancing drug allegations made against them in an Al-Jazeera report back in January, sources told ESPN’s Chris Mortensen.

Sources told Mortensen that free-agent linebacker Mike Neal, who also was named in the Al-Jazeera report, has not yet agreed to meet with the NFL.

This news comes on the heels of the NFL threatening to suspend the four players if they failed to comply with the league’s interview requests by Aug. 25. NFL vice president of labor policy and league affairs Adolpho Birch wrote in his letter to the NFL Players Association this week that the aforementioned players can be suspended for “conduct detrimental” by not complying, even if the league can’t prove any of the players actually used performance-enhancing drugs.

Harrison has agreed to meet Aug. 29 at the Steelers’ team facility, according a letter sent by the NFL Players Association to the NFL that was obtained by ESPN. It’s unclear whether the NFL will accept the conditions set forth by Harrison, who reportedly wants to limit questions to only the segment cited in the Al-Jazeera report in which he was identified.

It’s also unclear when Matthews and Peppers plan to meet with the NFL or whether Neal intends to follow in his fellow linebackers’ footsteps and comply with the league’s investigation.

Thumbnail photo via Charles LeClaire/USA TODAY Sports Images