GREEN BAY -- If anyone thought the Green Bay Packers were going to trade now-backup center Scott Wells -- including Wells himself -- the team made it fairly clear Tuesday that it's not going to happen when it released third-string center Duke Preston.

Preston, one of just two free agents signed by the team this offseason, struggled throughout training camp. Preston made 20 starts in four seasons in Buffalo, including 11 last year.

With three years remaining on the five-year, $15 million deal he signed in 2007, Wells seemed like a trade candidate after the Packers decided on their starting offensive line on Monday evening, committing to Jason Spitz at center and Josh Sitton at right guard.

Instead, coach Mike McCarthy said the Packers are lucky to have two starting-caliber centers on the roster, and it appears they're willing to keep both of them all season long.