An unofficial NFL clock begins ticking Monday for the Bears and defensive tackle Henry Melton. More than for just the Bears, in fact. Feb. 18 marks the first day when a team can place its franchise tag on a player. The Bears have been expected to tag Melton as they continue working toward a longer-term deal for a centerpiece of their defense. Of perhaps only slightly less interest to the Bears may be what other teams do with their tags. Denver is expected to tag Pro Bowl left tackle Ryan Clady and Cincinnati to do the same with tackle Andre Smith. Tackle was on the Bears’ wish list last offseason and tags have a way of adjusting the supply side of the market. Timing The Bears will not necessarily make any Melton move immediately. Indeed, a quick pull of the tag trigger could signal a harsh negotiating stance in a situation where that is anything but the goal. They had their franchise tag in play last year after contract efforts with running back Matt Forte stalled. The tag period opened on Feb. 20 and ran through Mar. 5. The tag wasn’t placed on Forte until Mar. 2. The organization had made it clear that it was not going to let Forte hit the open market and that GM Phil Emery regarded the tag, despite its unpopularity with players, as a negotiated part of the collective bargaining agreement. Nothing wrong with using it. The Bears have from Monday until Mar. 4 to apply their franchise tag to a player. The step does not mean that the tag price will be the player’s pay for 2013, but it buys time to work out a longer-term deal without other teams being able to make runs at their player without the protection of right to match any offer or receive two No. 1 picks as compensation.