In 2006, the Minnesota Vikings pulled off one of the most notorious moves in NFL history.
They poisoned the Seattle Seahawks.
The collective bargaining agreement the NFLPA and the owners agreed to included the franchise tag and transition tag - two levels of exclusive rights a team could use to keep a player on their team at the average of the five highest paid players at the position and the 10 highest, respectively.
Seattle, in an effort to save a few bucks, unwillingly ushered in the era of high-priced offensive guards by slapping the transition tag on left guard Steve Hutchinson.
The Vikings signed Hutchinson to a 7-year, $49 million offer sheet with the Vikings, with one provision in his deal being that, at any time, if Hutchinson was not the highest paid offensive lineman on the team, the full amount of his contract became guaranteed. Seattle offensive tackle and 2014 Hall of Fame inductee Walter Jones made more money than Hutchinson's contract, so Hutchinson would have had a $49 million guaranteed contract.
So the Vikings essentially eliminated the Seahawks' ability to fairly match the offer on the table for Hutchinson. They sought revenge by signing wide receiver Nate Burleson to a 7-year, $49 million contract that, not coincidentally, became fully guaranteed if he played five or more games in the state of Minnesota during the duration of his contract.
The Vikings got the better end of that deal. It was also the deal that would motivate Alan Faneca to seek his own windfall and way out of Pittsburgh. With no poison added, Faneca signed a 5-year, $40 million deal with the Jets after the 2007 season.
The poison pill provision has been eliminated from the latest CBA, likely due to the anti-competitive nature of it, but it was an epic game of tit-for-tat between two franchises in a league normally known for public displays of unity and control.
That said, Worilds can't sign a six-year, $54 million deal with the Oakland Raiders that becomes full guaranteed if Worilds ever plays for an owner with the last name of Rooney.