49ers quarterback Alex Smith suffered an injury to his left shoulder on Sunday against the Panthers. Carolina's Charles Johnson landed on Smith's shoulder and the quarterback is worried that the injury might be similar to the one that cut his 2007 season short. Smith plans to fly to London with the team and have an MRI there. "It's definitely the AC, I think. It's very similar," Smith said, referring to the acromioclavicular joint that's sometimes called a separated shoulder. "But I don't know to what I extent. There's not really much to say right now."