Harry How/Getty Images Ndamukong Suh

NFL free agency is coming, and it fills franchises and their fans with high hopes that signing the right players can transform their team and set it on the path to the Super Bowl.

The reality is that free agency does not have the same impact in the NFL as it does in the NBA and MLB. This is because rosters are much larger and rarely can one player make the difference except at the quarterback position. The chance of a true superstar being available on the NFL free agent market is much smaller than in other sports. The risk of injury plays a much larger factor in the NFL than in other sports. Teams make the same mistakes in looking at past performance rather than projecting future productivity as they do in other sports.

Albert HaynesworthThe limitations of the salary cap dictate that a small number of players on each roster in the NFL will receive mega contracts. Teams have to decide who is irreplaceable, non-fungible. All of the non-starters and certain positions are judged modular, and these players receive minimum or much lower contracts. Even though it is a team game and all positions are important, it is inherent that few players alter the chemistry so significantly that they can be transformational.

The players identified as "difference makers" are rarely allowed to hit the free agent market. Teams constantly extend these players contracts to insure that the contract never expires and turns into free agent status. Letting a critical star play through his final year without a new contract creates friction, uncertainty, and is bad business. In those cases where a new contract cannot be reached and the player is eligible for free agency, a team will use its franchise tag. Ndamukong Suh was an exception because his contract triggered a franchise number so high that exercising it would have crippled the Lions

Occasionally stars escape the franchise tag because teams just run out of cap room. The franchise tag can be dropped if a new contract with the player can be reached by July 17. Smart teams keep it available as a threat and use it to prod settlements rather than using it to tag. So if superstars are not available in free agency, the best 20 players who are free will reap a bonanza.

Free agency is one of the few paths outside the draft or trade to improve a roster. In every area of business, having to compete to acquire a talent or asset drives up the prices. Successful franchises have a shopping list prioritized and to achieve their top goals -- they will overpay. B+ players receive A+ contracts with big guarantees. If a player with a big guarantee does not produce, a team can be strapped with dead-cap money. Players from Super Bowl or winning franchises receive a premium as teams hope these athletes will bring a winning culture. Teams can make mistakes in overvaluing past performance of a player while not focusing on what his future performance will be. The ever-present spector of injury can always destroy the utility of any player.

​Intelligent signings in free agency can enhance a team roster and fill gaping holes. It certainly is a route to improving a team but rarely an avenue to transform a team.​

-- Leigh Steinberg has represented many of the most successful athletes and coaches in football, basketball, baseball, hockey, boxing and golf, including the first overall pick in the NFL draft an unprecedented eight times, among more than 60 first-round selections. His clients have included Hall of Fame quarterbacks Steve Young, Troy Aikman and Warren Moon, and he served as the inspiration for the movie "Jerry Maguire." Follow him on Twitter @leighsteinberg.

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