Salary matching

Salary matching is the rule that keeps trades roughly even. A team over the cap can't just take on a big contract; the salary it sends out and the salary it brings back have to land inside a set band of each other.

The room shrinks the higher a team spends. Teams with cap space skip the rule and simply absorb a contract into that space. Teams over the first apron get the tightest band of all, which is a big reason expensive rosters are so hard to reshape.