In the expansion draft each team had to leave a certain number of players that were currently under contract unprotected. You could not just not resign someone and say that is our unprotected player--if he ain't signed he isn't yours to barter with. If one of the players was selected, then they were allowed to remove one of the other players from the unprotected list. That was purportedly a big part of the Bosselli selection--if we agreed to take him then they would not pull back Walker or Payne. In the end probably irrelevant as V says.
The Art of War