"Brian Westbrook got plenty of cheers as he made his way to the field for the first time as a member of the 49ers, but most of the running the newest acquisition did Tuesday was with his mouth.

In a good way.

As the 49ers went through a two-hour workout in shorts and shells, Westbrook, wearing No. 20, was getting a crash course on the offense from running-backs coach Tom Rathman.

When he wasn't in discussion with Rathman, Westbrook was engaged in a long talk with trainer Jeff Ferguson as well as mingling with his teammates.

It's a new team, a new color, a new number and a new offense after eight years playing for a Philadelphia team that never changed its system during his tenure.

"I'm just trying to learn the offense, because I've been in the West Coast offense for eight years," Westbrook said. "The hardest thing to do is sit on the sidelines and watch, but it's probably the best way to learn."

Until Westbrook learns the playbook and terminology, he will impart the wisdom gathered from a career as one of the NFL's most prolific running and receiving backs.

Starting running back Frank Gore said he plans on being a good listener.

"He's been a great back in this league for a long time," Gore said. "I already started asking him questions. I feel he can help me get better."

Gore was an admirer of Westbrook with the Eagles as a way of measuring himself against the league's top backs."