RENTON, Wash. (AP) About to begin his third season, Justin Britt is embarking on learning his third position on the Seattle Seahawks offensive line.

He's had experience at tackle and guard and is now moving to center. That means a bit of stress having to learn yet another new position during the offseason.

''I'm definitely losing a lot of hair because of it,'' Britt joked Wednesday.

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The offensive line will be the mostly closely watched unit until the season opener on Sept. 11 because of all the changes. Gone are J.R. Sweezy and Russell Okung, lost in free agency. Patrick Lewis is back to being a backup at center for now. And if all goes to plan, Britt will be moving from left guard, where he played last season, to the center position.

It's a move that Seattle has pondered since drafting Britt in the second round of the 2014 draft. He started at right tackle that season, before being moved to guard during training camp before the 2015 season.

''Really I just want to start and play,'' Britt said. ''I love the challenge. To an extent it makes me feel more important, more involved, definitely. I feel like my abilities are capable of doing the job. I know the offense in and out. The hardest part is seeing it from the center perspective and getting the calls out quick.''

The offensive line was the most obvious of Seattle's problems early last season and part of that was instability at center. Drew Nowak won the job out of training camp but the Seahawks turned to Lewis at midseason and Seattle improved over the final half of the year.

The departures in the offseason, combined with Seattle drafting offensive linemen Germain Ifedi and Rees Odhiambo, helped prompt the decision to move Britt.

''Like anything, we just want to find the best five. We messed around with that with a backup thought in the past. Now it's creating more competition there,'' assistant head coach Tom Cable said. ''(He's) smart, tough, gets it. (He's) a good communicator.''

Britt said he was told of the decision after the NFL draft and he has since relied heavily on conversations with former Seattle center Lemuel Jeanpierre to help with the transition. Little things about the position are becoming repetitive and easier, like getting shotgun snaps back to the quarterback. Britt has also found himself spending more time watching film at this point of the offseason than in the past, including having the Seahawks video staff load tape of former center Max Unger on his tablet.

''After they moved me to guard I was like, `I better not put anything past them,''' Britt said. ''But at Missouri I played everything. ... Even last year when I started at left guard they had me playing both tackles in case of an emergency, I did reps at center in case of emergency, so I was prepared to be an emergency backup. I wasn't quite ready for them to be throwing me in there, but obviously I'm not against it.''

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