It's not a surprise that left guard Robert Gallery may not be ready for Seattle's season opener Sunday in San Francisco.

RENTON — It’s not a surprise that left guard Robert Gallery may not be ready for Seattle’s season opener Sunday in San Francisco.

Gallery’s status has been a question since he left Friday’s exhibition finale with a sprained knee. Neither he nor wide receiver Sidney Rice (shoulder) practiced Wednesday.

The surprise is the news of who might step in at left guard should Gallery not be able to play: rookie James Carpenter.

He was installed as the starting right tackle as soon as Seattle chose him in the first round of last April’s draft, and while he practiced some at left guard during the team’s short workout on Monday, coach Pete Carroll characterized that as more an exercise to develop flexibility rather than something Seattle was considering as an auxiliary plan should Gallery be unable to play.

Wednesday was different. From all appearances, Seattle is preparing Carpenter to play left guard if Gallery is unavailable.

“He is working there,” Carroll said of Carpenter at left guard. “He feels very comfortable there. He is a left-handed, left-sided guy in his background, so he did have to transition some to the right side. So he feels very comfortable.”

Carpenter played left tackle at Alabama, but it was not until the Senior Bowl in Mobile, Ala., that he was evaluated at guard.

While Carpenter at left guard, Breno Giacomini practiced with the first-unit line at right tackle. Giacomini was a fifth-round pick by the Packers in 2008, and Seattle signed him last year off the Packers’ practice squad.

“Breno has done very well in preseason,” Carroll said. “We’re really solid with him if that’s the way we go. We feel very good about him playing at right tackle. It just depends on how James goes, but he’s very much at home on that side. We’re lucky in that regard that we have a chance to have this option possibly. We’ll see what happens.”

While Gallery did not practice, he did run, according to Carroll.