Oakland Raiders Robert Gallery Courtesy AP Paul Sakuma

With the 2007 nfl draft rapidly approaching, fans and analysts are wondering if any of the top teams will make a blockbuster trade on draft day, involving any of the top five picks.

If you're one of these people, you can exhale and stop wondering. The chance of any of the NFL teams possessing top five selections - Oakland, Detroit, Cleveland, Tampa Bay and Arizona - trading down is slim.

Although most fans believe that trading a top choice is relatively easy, it is actually a very difficult proposition. Sure, the value of the top pick in the NFL draft may be extremely high, but the amount of salary that must be paid to any player selected in this spot is equally large.

So, in most cases, money becomes the primary issue. If a team in a lower position in the first round has salary cap problems, that team won't be too eager to move up and add potentially millions of dollars more in salary, even with the rookie minimum active salary, which helps teams compensate to some degree on draft day.

The difference in salary paid to a player chosen first overall in the NFL draft versus one taken eighth, for example, can be as much as several million dollars.

Some NFL teams are more salary conscious than others and are less likely to make a move, if they'll have to pay more, even if they covet a particular player. So, a team like Arizona, which is historically cheap, isn't likely to make a move on draft day, even though trading up for the rights to Wisconsin tackle Joe Thomas makes a lot of sense for the lineman-poor Cardinals.

Recent news might dispute this money theory, as Denver is rumored to be interested in trading its first- (21 overall), second- and third-round picks to Detroit for the number 2 overall selection. Of course, the Broncos would be saving plenty of salary dollars by not paying those players they would take in the rounds they'll trade away.

Plus, if this rumor is true, Detroit could save millions by moving down 19 spots.

So, we'll see how much money truly matters on draft day.