Also irl there's a hold for your own players
36. Can a team with cap room sign all the free agents it wants (up to the salary cap) and THEN re-sign its own free agents using the Bird exception?
A team's ability to do this is very limited. The team's free agents continue to be included in team salary. This charge is called the "free agent amount" (and is also frequently referred to as a "cap hold"). There may not be enough money available under the cap to sign another team's free agent, because the team's own free agents are taking up all their cap room.
38. Why do free agents continue to count against team salary?
It closes a loophole. Teams otherwise would be able to sign other teams' free agents using their cap room, and then turn their attention to their own free agents using the Bird exception. This rule restricts their ability to do that. It uses the player's current status (type of free agent, whether coming off a rookie contract, and previous salary) as a rough guideline to predict the amount the player is likely to receive in his next contract, and sets that amount aside in the form of a cap hold. But while it functions as a rough guideline, it's obviously not perfect -- for example, in 2005 Michael Redd's free agent amount was just $6 million, even though the Bucks intended to re-sign him for the maximum salary. By waiting to sign Redd last, the Bucks were able to take advantage of the difference by signing Bobby Simmons. Had they signed Redd first, they would not have had enough cap room to sign Simmons.
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