Key free agents: S Donte Whitner, CB Tarell Brown, K Phil DawsonWhere they stand: The 49ers are already off to a productive start to free agency. They re-signed receiver Anquan Boldin to a team-friendly two-year, $12 million extension earlier this week. Boldin was the team's top free-agency priority. No matter what happens once free agency starts Tuesday, the 49ers already accomplished Task 1. But that doesn't mean their work is over. The 49ers love their roster and they want to keep their talent.