The 49ers have completely and entirely overhauled a once ball hawking secondary coached by Jim Harbaugh from 2011 to 2014.
In that span, the 49ers have lost a half dozen players, including the likes of Deshaun Goldson, Donte Whitner, Tarrell Brown, Carlos Rogers, Chris Culliver and Perrish Cox.
In the last three NFL Drafts, the 49ers have added five players to replenish the well.
2013- Eric Reid (1st round)
2014- Jimmy Ward (1st round)
Dontae Johnson (4th round)
Keith Reaser (5th round)
Kenneth Acker (6th round)
They also countered the loss of Whitner by signing away from the Indianapolis Colts, Antoine Bethea, who is considered to be a better coverage safety than Donte was.