The Oakland Raiders have released Brandon Marshall in what was a surprising transaction.

Marshall signed a one-year, $4.1 million contract with the Raiders in March.

Antonio Brown lost his second grievance hearing over the use of his old helmet, but plans to move forward with a deal for an approved helmet in the near future.

Brown has been trying to wear his outdated Schutt Air Advantage helmet.

Brown, who participated in practice Tuesday wearing a certified helmet, took the practice field Sunday wearing what appeared to be an older helmet.

Antonio Brown practiced with the Oakland Raiders on Tuesday while wearing a certified helmet, Jon Gruden said.

"He's all-in and ready to go," Gruden said. "That's my understanding. Really happy to have him out here. He's a great player."

The coach told reporters that there's been "no distractions" for him or the team concerning Brown, whose second grievance hearing with the NFL will be presided by the same arbitrator from his first hearing and is scheduled for Friday morning, according to a source.

Antonio Brown has returned to training camp with the Oakland Raiders.

Brown took part in meetings on Monday after skipping practice on Sunday. Brown has been working to find a helmet he's comfortable using.

Mike Mayock issued a public ultimatum to Brown on Sunday to either be “all in or all out.”

Antonio Brown left training camp on Sunday over his anger being denied use of his helmet.

Mike Mayock issued an ultimatum to Brown in the process.

"You all know that AB is not here today, right?" Mayock told a group of beat reporters as practice began Sunday afternoon. "So, here's the bottom line -- he's upset about the helmet issue. We have supported that, we appreciate that. But at this point, we've pretty much exhausted all avenues of relief.

"So, from our perspective, it's time for him to be all-in or all-out, OK? So, 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's going to be a big part of it, starting Week 1 against Denver. End of story. No questions, OK? Just wanted you guys to know where we were. Fair?"

Brown has also been upset with the league not allowing him to wear his Schutt Air Advantage helmet.

The Raiders were excited about Brown's return and after he was a full participant in Saturday morning's walk-through, the team anticipated him practicing fully as soon as Sunday.

Antonio Brown isn't far away from a return to practice with the Oakland Raiders.

Brown has been dealing with a frostbitten foot and helmet issues, but he's "very close to practicing."

The wide receiver rejoined the Raiders on Tuesday.

Antonio Brown has reported to training camp with the Oakland Raiders.

"I'm extremely grateful to be here," Brown said. "I'm dealing with a lot of adversity. It's on the up and up, so I'm excited to be back and see my teammates and get in the groove of things here shortly."

The wide receiver was away from the Raiders while dealing with frostbitten feet from a cryogenic therapy chamber mishap and filing a grievance over wearing his old helmet.

There is no timetable for Brown to return to practice, but Jon Gruden fully expects the star to be ready for Week 1.

"We'll work him back in," Gruden said. "Obviously it's great to have him back. We've had a pretty good understanding -- in spite of what people think -- of what's going to happen. Now we're ready to get rolling."

Antonio Brown has lost his grievance to wear his old helmet.

Brown has threatened to retire from the NFL if he is unable to wear his old helmet as he believes it impairs his ability to see and catch the ball. Brown, however, confirmed he will play this season despite disagreeing with the ruling. 

Brown has reportedly stayed away from the Oakland Raiders at times due to his issues with the NFL's policy.

Antonio Brown has informed the Oakland Raiders he plans on not playing football again unless he can wear his old helmet.

Brown had a two-hour conference call with an independent arbitrator on Friday to argue why he should be permitted to wear his 10-year-old helmet. A decision could come as early as next week.

Brown believes the new certified helmet protrudes out and interferes with his vision as he tries to catch the football.

The Raiders have been sending Brown alternative helmets that are approved by the NFL.

Mark Davis has walked back comments made to The Athletic about the Oakland Athletics.

The Oakland Raiders and Athletics are co-tenants at RingCentral Coliseum.

"I am not sorry for the things I said," Davis said. "But I am sorry for the way I said them."

Davis had told The Athletic that the Raiders loved the A's as players and as a team, but that "the front office has been real p---ks."

"They've been really f---ing around with us up there, taking advantage of the situation," Davis was quoted in the story. "Which, it is their right to do it, but it makes it hard. Again, though, we love the players, we love the A's."

The Raiders are angered over a new Coliseum configuration created by the A's last winter that displaced 2,500 Raiders season-ticket holders.