In defense of the Spanish FA (just for the sake of playing Devil's Advocate) - I believe their rules do state that emergency signings can be made as a result of injury, but not because of a player sale.
The rules are obviously moronic (surely the only sensible route is to ban all player transfers outside of windows, as we do in England, and only allow free agent signings?), but they have been applied correctly in this case.
The rules are obviously moronic (surely the only sensible route is to ban all player transfers outside of windows, as we do in England, and only allow free agent signings?), but they have been applied correctly in this case.