Free agency in the NFL is perhaps the most unique period of player movement in all of professional sports. Teams that attempt to build a championship-caliber squad via free agency tend to fall flat on their faces, while organizations who rely on acquiring the key pieces in the draft flourish.
The team-centered nature of football places a tremendous amount of emphasis on scheme and game planning. It's impossible to look at a stat sheet and accurately prognosticate a player's production after shifting squads.
There are obviously exceptions to this rule. Nobody ever thought Peyton Manning's move from Indianapolis to Denver would affect his production. However, for every Peyton Manning, there is an Albert Haynesworth, Nnamdi Asomugha, Laurent Robinson or John Carlson.
Free agency can be beneficial for a team looking to fill holes on its roster, but it's rare that a big-name signing ever lives up to his contract. The elite general managers across the league have the ability to attract quality players that come with reduced price tags.
Let's take a look at four players in the upcoming free-agent class that could have some surprise value in 2013.