RAIDERS GET FIRST GO AT NEW STAR RECEIVER

NAPA — That’s just a little preview, a little taste, so imagine him being in on every play with (Derek Carr) back there,” wide receiver J.J. Nelson said. “It’s going to be fun. It’s going to be exciting. I’m looking forward to lighting up the scoreboard.”

Brown went through warmups and drills in full pads, and then through one session with receivers working one-on-one against defensive backs. Brown caught most everything thrown his way, and on his last two receptions scored one touchdown on Trayvon Mullen and then another against Gareon Conley.

He then adjourned to the weight room area, presumably for treatment of a still undisclosed injury, getting in about about 90 minutes of work on the field with his teammates.

“He’s getting close. And hopefully after the day off tomorrow he’ll get closer,” Raiders coach Jon Gruden said. “We need him on the grass. We need to get him going. And he’s champing at the bit. He’s not a real patient guy. Hopefully it’ll be sooner rather than later.”

Brown has yet to speak to the media through four days of media, and Gruden and the Raiders have declined to give the nature of the injury or when and how it occurred. A source initially told the Bay Area News Group the club was aware of the issue two weeks before camp began and that he’d miss “probably” a week.

That would make it conceivable that Brown could be full go Aug. 7 and 8 next week when the Los Angeles Rams visit Napa for two days of joint practices. Or Brown could be good to go before then.

Even a little bit of Brown was a spectacle an overcast morning. His every move during warmups was dutifully recorded for the HBO “Hard Knocks” camera crew, boom microphone tracing most every step.

After nearly every rep, Brown went to the sideline to talk with a personal trainer who dealt with no other Raiders. Brown took his right shoe off to have his foot looked at before putting it back on as he and his trainer walked over to owner Mark Davis and former Raiders linebacker Bill Romanowski for a conversation.

Shortly afterward, Brown made it back on the field, where he victimized both Mullen, the Clemson rookie, and Conley, the third-year cornerback.

Brown and his trainer then walked toward the field house and weight area, done for the day before 10:30 a.m.

Pressed for specifics on Brown’s injury, Gruden said, “I’m not going to get into all of it really. He’s day to day and it’s nothing serious. It’s something that it’s going to take a couple days. We’ll keep you posted.”

Conley and other Raiders defensive backs are eager to get more reps against Brown at full speed as camp goes on.

“Every chance I get I’m going to try and go against him,” Conley said. “I always ask him questions about where and when he breaks, what he’s doing at the line, down the field. It’s going to make me better in the long run.”

Nelson said there have been no signs of frustration from Brown.

“A.B. is A.B. He’s the best in the league,” Nelson said. “He knows and we know what he brings to the table. We know when he comes out here, he’s going to bring that energy, he’s going to make plays in training camp. It’s Day 4? We’ve got a whole lot of football to play. We’re just waiting.”

More Day 4 highlights and notes:

— Having practiced four consecutive days, the Raiders have a day off Wednesday as mandated by the collective bargaining agreement.

— Another day, another eye-opening play from tight end Darren Waller, who made a leaping sideline downfield catch against Keisean Nixon on a throw from Nathan Peterman.

“Since he’s been here he’s been one of our most impressive players, physically and athletically,” Gruden said. “And he’s smart. And he’s got an unbelievable opportunity. He and (Foster) Moreau, our young tight end from LSU, really have helped our two tightend set.”

— Linebacker Tahir Whitehead had the hit of the day, dropping DeAndre Washington in his tracks to break up a short pass from Carr.

— Mullen, the secondround pick from Clemson, showed good length and recovery in breaking up a long pass thrown by Mike Glennon in the end zone against the speedy Nelson.

— Brandon Marshall practiced for the fourth straight day and at one point intercepted a Glennon pass. The former Broncos linebacker rehabbed an undisclosed injury throughout the offseason and rarely saw the field.

“We knew if we can get him to training camp and get him rehabbed, he’s one of the best coverage linebackers in football,” Gruden said.

— Early indications are Peterman may be a little ahead of Glennon in the battle to back up Derek Carr. Peterman had some atrocious games as a starter in Buffalo.

“This Nate Peterman is growing on me,” Gruden said. “I know he’s had some nightmare performances in the NFL. But when you watch the film you can see why. It’s not all his fault . . . he was an opening day starter for the Buffalo Bills last year. I take that very serious . . . he’s starting to get his confidence back.”

— The Raiders donated $5,000 each to the high school football programs of Skyline, Castlemont and Oakland of the Oakland Athletic League as well as Madison Park Academy and Monte Vista as part of the Dick’s Sporting Goods “Sports Matters program.”

Raiders players and coaches also donated to bring the total for the five schools to $25,000.