If there was one position the Seattle Sounders needed to address this offseason, it was their depth at center mid. After Monday's signing of 11-year MLS veteran Nathan Sturgis, the Sounders have certainly done that.

Sturgis had been on trial with the Sounders since the start of training camp and had been drawing positive reviews from coaches throughout. He'll likely be competing for backup minutes along with the likes of Cristian Roldan and Michael Farfan.

Also helping his case was his familiarity with the Sounders, after having played here from 2009-2010.

"He's technically very sound, has two good feet, hits a good ball, finds his passes," said Sounders head coach Sigi Schmid, noting that Sturgis also played for him at the 2005 Youth World Championships. "He's good guy in the locker room, gets along with the guys and wanted to be here, which is an important aspect for us.

"He gives us a little bit of a veteran presence coming off the bench in the midfield. It's a long season, you need some of those guys as well. Our competition is good. When I look at our trainings, not only from the starting group, but there's good football from the second group and I think Nate helps that."

Sturgis, still just 28, has bounced between MLS starter and reserve throughout a career that has seen him play for eight different teams, including two stints with both the Sounders and Houston Dynamo. Along the way, he's been a center back, a right back and a midfielder. The Sounders seem to see him mostly as a center mid. He'll be eligible to play immediately.

Damion Lowe update: The Sounders confirmed that the Generation Adidas center back is on trial with Minnesota United of the NASL. In two years since being drafted, he's shown promise but injuries and inconsistency have kept him from making a MLS appearances.

Roberto Chen update: GM Garth Lagerwey said the Sounders' roster is effectively full, seemingly suggesting that there's no room to sign the Panamanian center back. But Chen continues to train with the Sounders, and there are still a lot of moving parts. If Lowe were to go on a season-long loan to United, that would open a roster spot and an international roster spot. The Sounders could also put Román Torres on the disabled list, which wouldn't save any salary cap room, but would create some roster space. None of that accounts for Obafemi Martins' spot, either. Once that deal is finalized, a whole host of moves could follow.