The Oklahoma City Thunder have achieved a remarkable amount of success by establishing and sticking to a few central beliefs. It was that fidelity to those principles that led them to trade James Harden because of a contractual dispute.

According to sources with knowledge of the team's thinking, the Thunder believe their players will ultimately support the controversial decision to send Harden to the Houston Rockets in a blockbuster deal that breaks up the core that reached the NBA Finals last season.

The Thunder maintain a philosophy that the individual sacrifices for the whole. In this case, that would have meant Harden agreeing to accept less than the maximum amount for a four-year extension, which was $60 million. Reportedly the Thunder's final offer was in the range of $55 million for four years.

Over the past few days, as extension talks reached a climax ahead of the Oct. 31 deadline, sources said, Thunder GM Sam Presti informed Harden that if he was not willing to accept a franchise-favorable contract, such as the kind that Serge Ibaka accepted recently, after other Thunder players had done likewise, then Harden would be traded. This was made clear in discussions with Harden and his agent Rob Pelinka, sources said.

During the contract talks that have been ongoing since July, Presti provided a reference point -- some might call it a threat ... regarding the discussions: the Jeff Green negotiations from a couple of seasons ago. That's when the Thunder were unable to get a contract extension done with the popular forward and traded him, in a surprising move, to get assets and prevent Green from getting to free agency the following summer. Harden would've been headed for the same situation if he had not agreed to an extension by Wednesday.

The Thunder, it was said during the talks, cannot afford to let players get to free agency, with the additional cost and risk involved. From the player's perspective, this is rigid. From Presti's perspective, it was the way to do business in a franchise with more limited resources than rivals and in a market where free agents are often overpaid.

Presti was attempting to force through a contract that would help soften the blow of the increased luxury tax that starts in the 2013-14 season, when Harden's new deal would've kicked in.

Over the past several years Ibaka, Russell Westbrook, and Nick Collison have structured new contracts in ways that would ease the Thunder's coming tax burden. In each case, the player accepted a deal for less than his estimated market value had he waited for free agency. Collectively these moves are saving the Thunder millions in salary and potentially tens of millions when accounting for future tax payments. That money, in theory, is used to sign their talented teammates.