A-Rod and Boras
Alex Rodriguez is scheduled to make $27 million a year for the next three years after this season is complete. He can elect to terminate this contract in order to receive more money, upwards of $32 million a year, and tacking on additional years to his contract that would likely be his last huge money contract, or at least the last one that would end in his "prime".
Rodriguez turns 32 later this month, and at the end of his current contract he'll be 35. I'm no master of economics, but in all likelyhood the contract that Rodriguez would receive to play into his late 30s/early 40s would be larger if he were to sign an extension now than if he were to play to the end of this contract and entering the free agent market at the age of 35, when most players are seeing a decline in statistics (under investigation San Francisco outfielders excluded).
Agent Scott Boras' threats (we'll just say they're his instead of Rodriguez just to make him look better and make an agent the villian, which is easy enough to do) to terminate Rodriguez' contract at the end of this season and test the free agent market are geared solely at one team - the New York Yankees. Well, that's obvious, since the team with the most to lose if Rodriguez does this is the Yankees, who lose one of the best offensive players in baseball, and receive no compensation for it.