Cable hopes to start narrowing the center competition down in training camp and sort things out, "somewhere in the preseason. When? Who knows? I think it's going to show up pretty quickly though."

Sokoli, a sixth-round pick who played defensive tackle at Buffalo, is making quick progress at his new position, Cable said.

"He's on it right now," he said. "I wouldn't say he's behind. He might even be a little bit ahead. A ferocious competitor, so I think that's given him the opportunity to stand there and kind of fight his way through this learning process, and it's a ton. It's a big hill to climb, but I think he's doing well."

2. The depth at receiver is impressive

Douglas McNeil III made one of the better catches of practice, a leaping grab in the end zone on a pass from R.J. Archer. Not long after that play, undrafted rookie Deshon Foxx came up with an impressive sliding catch, a play he finished by jumping up, having not been touched, and sprinting for the end zone. That those two players stood out Tuesday, two players fighting an uphill battle to make the roster, highlights the solid depth Seattle has built at receiver heading into the 2015 season.

Third-round pick Tyler Lockett was the big offseason addition for Seattle, but he's not the only reason the Seahawks are better at receiver than they were a year ago. Chris Matthews development, highlighted first by his role on special teams, then by a huge Super Bowl performance, has him poised to take on a bigger role in 2015. McNeil III's 6-foot-3 size and athleticism makes him an intriguing, if still unproven prospect, and we still haven't even mentioned Doug Baldwin, Jermaine Kearse, Ricardo Lockette or last year's draft picks Paul Richardson and Kevin Norwood.

3. Even All-Pros have to earn their stripes