Sean Locklear knows there's added pressure that comes with playing left tackle, even if it's just the reverse of what he's learned on the right side.

Locklear will get the start at left tackle for the Seattle Seahawks on Sunday against the St. Louis Rams. He's replacing nine-time Pro Bowl selection Walter Jones, who is out following his second knee surgery in eight months a few weeks ago.

That means the responsibility for protecting the backside of quarterback Matt Hasselbeck falls to Locklear. It will be the third start for Locklear at left tackle in the last two seasons.

Jones and center Chris Spencer are out for Seattle. They might also be without receiver Deion Branch, who did not participate in his second straight practice (hamstring) on Thursday.