The Tennessee Titans are getting ready for their second preseason exhibition game, and yet star running back Chris Johnson is nowhere in sight.

Johnson, inarguably the best running back in the league the last three seasons, wants to be paid as such (and then some). The Titans have indicated that they're willing to talk about it, but Johnson so far has stayed away from camp. The Giants' Osi Umenyiora and Eagles' Desean Jackson also held out briefly, but both have now reported.

NFL preseason holdouts are nothing new. Sometimes it's rookies who want to get every last dollar they can (though this might go out of the window next year once the new CBA's rookie slot money system kicks in); sometimes it's veterans who wish to tear up their old contracts because their production demands better; and sometimes it's just guys who don't want to sweat through the rigors of training camp.

Whatever their reasons, holdouts are usually resolved before the first real game is played. But there are instances where the negotiations get very nasty as both sides dig in, resulting in the player's missing an entire season. Sometimes these rancorous confrontations end up with the players being traded. Every case has its own unique story, and these are our Top 10 Most Memorable NFL Holdouts: