In NFL free agency, it's important to exercise discretion when making moves. Sometimes the moves you don't make can be more significant than the ones you do. Even if your team needs an upgrade at a position, paying top dollar in an inflated market for a player can be costly. Years down the line, it is those big flops that hurt a franchise unable to rebuild as it lives out its impetuous mistake of trying to find a quick fix.
So which players come with a "buyer beware" tag in 2013? Here are the top 10 when viewed through the Pro Football Focus prism.
Note: More detailed explanations of the advanced statistics used below can be found here.
Defense
Cary Williams, cornerback
2012 team: Baltimore Ravens
Williams
If reports are to be believed, Williams bet on himself by turning down a three-year, $15 million contract from the Ravens last year. Two postseason interceptions, to go with four in the regular season (along with 11 pass deflections), might suggest that was a wise move from Williams.
But watching the tape a little closer doesn't leave you quite as impressed. Williams gave up 39 first downs in the regular season and six more in the postseason, meaning his combined 45 first downs surrendered were the second highest of all cornerbacks. He wasn't a shutdown corner but rather someone teams moved the chains on. He may be looking for top cornerback money, but teams shouldn't be fooled into thinking he is one.