The 49ers' recent exodus included the losses of defensive mainstays Justin Smith, Patrick Willis, Aldon Smith and up-and-comer Chris Borland, but veteran safety Antoine Bethea sees a new foundation rising.
"We'll look really different than we did last year," Bethea on Tuesday told KNBR.
Bethea likened the approach to the Jim Harbaugh era, when the 49ers' defense consistently ranked among the top in the league under coordinator Vic Fangio.
"We're going back to similar to when Vic Fangio was here, you know, our front seven would stop the run and get after the quarterback, and let the DBs sit back and make plays.