The Packers made sure defensive back Sam Shields didn't hit the open free agent market by getting him to agree on a four year contract extension over the weekend worth a reported 39 million dollars. Shields' agent, Drew Rosenhaus tweeted late Saturday afternoon that the deal was done and Shields also posted a tweet that he's happy to be coming back to the Packers. The contract pushes the 26 year old into the upper echelon of defensive backs in the NFL and will make him the third highest paid player on the team behind only Aaron Rodgers and Clay Matthews. The contract reportedly includes a signing bonus of 12.5 million dollars but will also be relatively salary cap friendly to the Packers in 2014 with an expected cap value at more than five million dollars. General Manager Ted Thompson clearly identified Shields as a player they want back and more importantly, might be difficult to replace. Unrestricted free agents were able to size up the market over the weekend and teams can start signing them to contracts Tuesday afternoon. While the price for Shields appears a bit high, the Packers still have plenty of breathing room under the cap to hopefully reel in a few more of their 17 unrestricted free agents. B.J. Raji spent the weekend mulling over a four million dollar, one year deal with incentives while several other players like James Jones, Mike Neal and Evan Dietrich-Smith haven't heard from the team and will likely consider offers from other suitors.