Though Antonio Brown was expected to rejoin his teammates this week, Oakland Raiders general manager Mike Mayock told reporters Sunday that the wide receiver was not at practice due to his ongoing helmet issue.
Mayock added the Raiders supported Brown through his grievance with the NFL and search for his preferred helmet model, but have to know whether the star receiver is "all-in or all-out."
"We're hoping he's back soon," he said. "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 1 against Denver."
The news comes as a surprise despite the wideout's eventful offseason. Oakland head coach Jon Gruden said Brown participated in the team's Saturday walkthrough and was nearing full participation in practice.
Brown is in the midst of an ongoing fight with the NFL to wear a helmet that's no longer approved. His camp is still searching for a Schutt Air Advantage model manufactured within the past 10 years.
The seven-time Pro Bowler reportedly found a 2014 edition of his preferred model, but it recently failed a test required by the league and can't be used.
Brown was also dealing with frostbitten feet stemming from a cryotherapy chamber mishap. He didn't suit up for the Raiders' second preseason contest but did run drills during pregame workouts.