Raiders TE Brandon Myers, who has the early edge in a wide-open battle for the starting job, suffered a shoulder injury midway through practice and went to the locker room to be examined. Minutes later, he left the practice facility with a trainer.

Raiders coach Dennis Allen said he wasn’t sure how severely Myers was hurt.

Myers was hurt when SS Mike Mitchell took him to the ground. The ultra-aggressive Mitchell said he’s still learning how to “be a professional” and rein himself in during practice.

“That is, keeping everybody up, staying off the ground,” Mitchell said. “There was a play today, Brandon Myers, one of my best friends on the team, just competing, kind of fell on his arm a little bit. I hope he’s going to be OK. I still got to learn it’s practice and avoid those things.”

WR Darrius Heyward-Bey (knee) and OT Zach Hurd (head) were also injured and had to leave practice early. Allen said he believes both of those injuries are minor.

Goodson making progress: RB Mike Goodson, who suffered a neck injury during practice Tuesday, spent time on an exercise bike and also on the sideline watching practice.

“I’m good, man,” Goodson said. “Getting back, rehabbing and starting to feel like myself again. … Right now it’s just a little soreness left in my neck, kind of like having a crick in your neck when you wake up in the morning or something like that. A little more intense than that, but that’s pretty much it.”

Goodson said he has no timetable for his return to practice.

“Soon as I can, man, soon as they give me the green light to go, I’m going to be ready to go,” Goodson said.

Goodson was injured during a collision with LB Philip Wheeler. He was taken via ambulance to Queen of the Valley Medical Center in Napa, but a CT scan and MRI were negative and he was released that evening.

“It’s like any play, you’re going hard,” Goodson said. “Like anything on the field, you’re just a football player, just playing football. You hit somebody. So when I laid there immediately it was just a hit, so I tried to get up and I couldn’t, I couldn’t feel my neck, so it was pretty tough.”

Goodson thanked teammates, including Tawain Jones and Richard Seymour, for sticking close while he was on the ground, waiting for the ambulance to arrive.

“I could hear their voices talking and that kind of helped,” Goodson said.

Allen keeping plans under wraps: Allen said he won’t tell his players -- or the media -- how long they’ll play Monday night against Dallas. They’ll find out as the game goes along.

“I want our players focused on going out and playing and not how many reps they’re going to get,” Allen said. “I won’t tell them until they’ve played the game, and I tell them they’re coming out. Because there’s only one way you can play the game, and that’s getting your mind right, and go out and compete. And that’s what I want those guys to do, whether they’re ones or twos or threes.

“I think a lot of times when you tell them, hey, you’re going to play one quarter, you’re going to play 10 snaps, whatever the case may be, there’s a little bit of a mental letdown, and I don’t want that.”

Extra points: Starting SS Tyvon Branch missed practice because of back spasms. WR Denarius Moore (hamstring), WR Eddie McGee (hamstring), RB Taiwan Jones (hamstring), DT Richard Seymour (knee), DE Jack Crawford (foot) and P Shane Lechler (knee) remained sidelined.

Follow Raiders reporter Eric Gilmore on Twitter @CBSSportsNFLOAK.