NFL teams are prepared to use restricted free-agent tenders, even if they don't know if the tags will be binding in the uncertain labor climate, according to multiple league sources. Teams are trying to restrict the ability of some of their key players to sign with another club even if their contracts are up. The big question, of course, is whether these tags are binding once there is a new collective bargaining agreement. When told that teams will be using restricted free-agent tenders, one agent said: "The boxing gloves are on."