'All in or all out': Oakland Raiders GM issues warning to Antonio Brown as helmet saga rumbles on

Oakland Raiders management appears to have drawn a line in the sand with star receiver Antonio Brown, asking him if he is "all-in or all-out" after he missed practice once again amid a row with the NFL over helmet safety.

Brown was a high-profile addition to the Raiders roster in March as the franchise traded two draft picks to acquire the 31-year-old former Pittsburgh Steelers star to (at the time) the biggest contract ever handed to a player in his position.

Since then though, Brown appears to have worn the team's patience thin. He was missed several of the team's pre-season practices in part due to a battle with league officials due to the safety of his helmet, and also because of severe frostbite on his feet which occurred after he failed to wear the correct footwear while undergoing cryotherapy treatment in France. 

"You all know that AB is not here today, right?" Raiders General Manager Mike Mayock said to reporters on Sunday.

"So, here's the bottom line. He's upset about the helmet issue. We have supported that, we appreciate that.

"At this point, we have pretty much exhausted all avenues of relief. So, from our perspective, it's time for him to be all-in or all-out.

"We're hoping he's back soon. We've got 89 guys busting their tails. We are really excited about where this franchise is going and we hope AB is going to be a big part of it starting week one against Denver. End of story."

Brown's preferred helmet, the Schutt AiR Advantage, has been phased out under a safety policy enacted by the NFL and the players' union, a decision which affected around 30 players in the league.

Tom Brady and Aaron Rodgers are understood to have also been required to change their helmets, but Brown's unhappiness comes from elements of the new design which he says obstructs his line of sight. Brown attempted to find a loophole by locating a helmet less than 10 years old which wouldn't yet require testing, but reports on Saturday states that the NFL located one themselves and performed safety tests - which it failed.

Brown had previously suggested that he may consider retirement if the helmet saga isn't resolved to his satisfaction, a move which could cost the player tens of millions of dollars in lost earnings from one of the largest wide receiver contracts in history.