After one of the strangest absences the NFL has ever seen, Antonio Brown is reportedly ready to rejoin the Oakland Raiders

AP Photo/Jeff Chiu

Antonio Brown.

• Antonio Brown is set to return to Raiders training camp after his bizarre absence.
• Brown was attempting to find a way to wear his old helmet, which no longer met safety standards put in place by the NFL.
• After briefly threatening to sit out if he were forced to change helmets, Brown lost his grievance with the league and decided he was ready to get back to camp.
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After an extended absence from training camp, Antonio Brown looks ready to begin preparing for the season at Raiders training camp.

Just days ago, Brown was threatening to sit out the year while attempting to convince the NFL to let him continue to use his old helmet. Now, Brown has officially lost his grievance with the league and looks set to get back to practice soon.

"While I disagree with the arbitrator's decision, I'm working on getting back to full health and looking forward to rejoining my teammates on the field," Brown wrote in an Instagram post. "I'm excited about this season appreciate all the concerns about my feet!"

Brown was one of the biggest acquisitions of the NFL offseason, with the Steelers trading the All-Pro receiver in exchange for draft picks. They then signed him to a three-year deal worth $50 million that included $30 guaranteed.

But despite the Raiders' investment in Brown, his tenure in Oakland didn't start according to plan. Reports came out that Brown was dealing with a foot injury that prevented him from practicing at full speed. It was later revealed to be frostbite caused by using a cryotherapy machine without the proper footwear.

Read more: Antonio Brown's mysterious foot issue is reportedly frostbite caused by not wearing proper footwear in a cryotherapy machine

From there, things got more bizarre.

Reports came out that Brown had gone "radio silent" with the team while attempting to figure out a way to play the 2019 season with his old helmet.

With Brown's helmet more than 10 years old, it would no longer meet the standards of new rules set by the NFL. Brown did his best to keep his old helmet, even going as far as reportedly repainting his old one.

Read more: Antonio Brown reportedly had his old helmet repainted after being told he couldn't use it but was caught because it looked noticeably off

When his efforts fell short, he filed his grievance with the league, which he officially lost on Monday before making his Instagram post.

Brown isn't the only veteran player dealing with frustrations regarding the league's helmet policy.

Patriots quarterback Tom Brady and Cowboys tight end Jason Witten have both also expressed their struggles adjusting to new helmets.

"I've been experimenting with a couple different ones, and I don't really love the one that I'm in, but I don't really have much of a choice," Brady said while appearing on "The Greg Hill Show" on sports radio WEEI. "So I'm just trying to do the best I can to work with it."

Read more: Tom Brady forced to change helmets because of NFL rule, says it's a difficult adjustment

Ultimately, Brown, Brady, and Witten have all conceded to the rule. In Brown's case, he's gone as far as putting out an open call on Twitter for a version of his old helmet that was made within the past 10 years.

With three weeks of preseason left, Brown better hope he finds his new helmet soon.

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