Brown filed another helmet grievance against the NFL on Monday.
Raiders wide receiver Antonio Brown joined Oakland's practice at training camp on Tuesday with a certified helmet, according to head coach Jon Gruden.
Brown's helmet drama has been the dominant storyline of Oakland's offseason. The four-time All-Pro threatened to retire on Aug. 9 if he was not permitted to wear his now-outlawed Schutt Air Advantage helmet. He then filed a helmet grievance against the NFL but lost his case with an independent arbitrator.
Oakland's star receiver now appears to have found a solution to his helmet issue, per Gruden.
"It's a certified helmet. He's all-in, ready to go." Gruden said on Tuesday.
Raiders coach Jon Gruden was asked if Antonio Brown showing means he's all-in, smiled and responded, "Is that some sort of joke? Yeah, he's in, all-in, that's what he said."— Albert Breer (@AlbertBreer) August 20, 2019
On the kind of helmet Brown's wearing, Gruden said, "It's a certified helmet. He's all-in, ready to go."
According to the NFL Network's Ian Rapoport, Brown wore a league-approved Schutt Vengeance Z10 LTD helmet at Tuesday's practice.
#Raiders WR Antonio Brown wore a Schutt Vengeance Z10 LTD helmet today in practice, per source. It is among the 34 helmets approved for use after the NFL-NFLPA laboratory tests were conducted early this year and sent to players in April. It’s in the green grouping of helmets.— Ian Rapoport (@RapSheet) August 20, 2019
Raiders GM Mike Mayock expressed frustration with Brown's situation on Sunday.
"At this point, we've pretty much exhausted all avenues of relief," Mayock said. "So from our perspective, it's time for him to be all in or all out."
The Raiders acquired Brown in a trade with the Steelers in March. Brown has caught 100-plus passes in six-straight seasons.