Antonio Brown's time with the Raiders has already taken an ugly turn with reports that he's livid over new helmet rule, battling a strange injury, and has gone 'radio silent'

• Antonio Brown's time with the Oakland Raiders has taken a bizarre and ugly turn in training camp.
• According to reports, Brown has been missing from Raiders training camp, in part because he is livid about a new NFL rule that bans the helmet he has worn for nine years.
• Brown is reportedly threatening not to play football if he can't wear his old helmet.
• Brown has also been dealing with a strange foot injury that has limited him and is said to be frostbite caused by a cryotherapy chamber.
• Teammates reportedly do not know where Brown is, with one report saying the star receiver has created "an aura of mystery and uncertainty."
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Things between the Oakland Raiders and Antonio Brown have taken a bizarre and ugly turn early in training camp.

Brown, the star wide receiver the Raiders acquired in a trade with the Pittsburgh Steelers in March, has reportedly been missing from camp in recent days due to a strange foot injury and anger over a new helmet. NFL Network's Mike Silver reported that the events surrounding Brown have created an "aura of mystery and uncertainty."

On Friday, Chase Williams of Pittsburgh's WXPI reporting that Brown has gone "radio silent" and the team did not know where he is.

According to ESPN's Adam Schefter, Brown has told the Raiders that he won't play football unless he gets to wear his old helmet, which has now been banned by the NFL because it is no longer certified by the National Operating Committee for Standards and Athletic Equipment (NOCSAE). Brown, who filed a grievance against the NFL to wear his old helmet, believes the new helmets interfere with his ability to catch the ball, according to Schefter.

Silver on Friday that Brown has been livid over the new helmet rule for months.

According to Silver, the NFL informed all teams that equipment managers had to remove banned helmets and that teams in violations of the rule would face discipline.

At organized team activities (OTAs) in May, Brown tried to push back on the new helmet rule and wear his preferred helmet, according to Silver. When he was denied, Brown "loudly voiced his displeasure" with the rule and later "stormed out" of the facility.

According to Silver, it has been a recurring theme, with Brown trying to sneak his old helmet into practices, even going as far as to wear an old helmet that was re-painted to look like the new ones.

A source told Silver that Brown's insistence on wearing the old helmet is the "the most insane thing I have ever heard. I don't know why it's so important to him. It doesn't make any sense."

With Brown still missing from camp, a Raiders player told Silver: "[Brown's] still freaking out about it. He hasn't been here for awhile, and no one knows where he's at."

According to Michael Gelkhen of The Las Vegas Review-Journal, Brown has not participated in a full practice at camp and has missed 10 of 11 practices entirely.

Brown has also been limited due to a mysterious foot injury. Pro Football Talk's Chris Simms first reported that Brown's foot - which appeared to be severely blistered in a photo he posted on social media - had frostbite after Brown did not wear the proper footwear in a cryotherapy chamber. Schefter also reported it was frostbite.

Brown was said to be seeing a foot specialist, with Raiders head coach Jon Gruden telling reporters on Tuesday that Brown was "gathering information."

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

Silver also reported that when Brown has been around the team, he has been a distraction. According to Silver, that Brown has shown up late to meetings and has often spent his time in meetings "perusing his bank accounts and 'liking' photos on Instagram."

There have clearly been mixed signals coming from Raiders camp. Gelkhen had reported that Brown was expected to re-join the team in the near future, but this was before Schefter's report that Brown said he will refuse to play with the new helmet.

The Raiders told Schefter they are "aware and supportive of Antonio Brown, but [have] no further comment."

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