SANTA CLARA — Chase Beeler walked into the San Francisco 49ers' locker room for the first time and felt right at home.
Everything from the motivational signs plastered along the walls to the coaching staff to the playbook was familiar.
Maybe only to the rookie.
After playing under coach Jim Harbaugh at Stanford, Beeler is competing for a spot on a 49ers offensive line that has more holes than highlights at the moment. For everyone but Beeler, the O-line overhaul has been one of the biggest changes this year.
The preseason opener is Aug. 12 at New Orleans, and there might not be a bigger learning curve than the offensive line.
San Francisco already has parted ways with two of last season's starters, guard David Baas and center Eric Heitmann, and are relying on improvement from within after doing little in free agency. Baas signed with the New York Giants and the 49ers released Heitmann.
The key returning members are left tackle and leader Joe Staley and two 2010 first-round draft picks, right tackle Anthony Davis and left guard Mike Iupati. Both started every game as rookies.
Adam Snyder is the front-runner to move from guard to center. Beeler could also play center or switch to guard, and the team will likely sign at least one offensive lineman who could start.
"I've got high hopes," Harbaugh said. "Good expectations, again, that we can keep improving with an offensive line that there's been some shake-up, especially with a new system. It's so important that those guys play well together. I think they got the right makeup to do that."
Staley and Snyder took in some rookies during informal offseason workouts this summer, leading offensive line meetings during two separate four-day minicamps.
The competition on the line figures to last through training camp and maybe beyond.
San Francisco S C.J. Spillman signed his one-year tender.
The 49ers signed free agent fullback Jack Corcoran to a three-year deal.