Michael Sam, who hopes to become the first openly gay athlete to play in a regular-season NFL game, has been released by the Dallas Cowboys.
The defensive end, 24, spent the first seven weeks of the season in the 10-man practice squad and never made the 53-man roster.
"I will take the lessons I learned here and continue to fight for an opportunity to prove that I can play every Sunday," he tweeted.
Sam is now free to sign for any team.
The Texas-born player was picked by the St Louis Rams in the seventh round of the draft in May.
When he was cut by the Rams in late August, the Cowboys picked him up and placed him on the practice squad.