Jeff Green became odd man out with rise of Russell Westbrook, Serge Ibaka

In one of the biggest surprises of the trading deadline, the Thunder sent the versatile swingman to the Celtics and dealt away a significant piece of its young, talented core. Green is a starter, a contributor, not to mention a big-time ballplayer.

No player that the Thunder acquired Thursday is as good as he is. Not Nazr Mohammed. Not Nate Robinson. Not even Kendrick Perkins.

So, why trade Green?

He'd become the odd man out.

Even though he has been a cornerstone player since the franchise moved to town three years ago, you could see a shift during the past year or so. It wasn't an overnight move but rather a slow, steady change.

First, Russell Westbrook emerged as a point-guard powerhouse. Thunder brass always contended they saw the potential for greatness in him, but I'm not sure anyone ever projected this from Westbrook. He strikes fear into opponents with his ability to shoot, drive, score, pass and defend.

He is a game-changer.

More than that, Westbrook is the perfect complement to Durant. He is the fire to Durant's ice, the grit to his smooth, the Robin to his Batman.

Not so long ago, Green was Durant's sidekick. They were the yin and the yang. They were the one-two punch.

Westbrook's emergence changed Green's place on the team.

Serge Ibaka's cemented it.

Green has been playing out of position for as long as the Thunder has been in Oklahoma City. Occasionally, he'd have a chance to play small forward, but if the Thunder wanted its best players on the floor at once, Green had to play power forward. That wasn't a spot Durant could play. Ditto for Thabo Sefolosha.

Green was forced to play out of position because he could. He was undersized but versatile enough to manage.

Then along came Ibaka.

Last year, we saw glimpses of what he could do. This season, his scoring and rebounding, his defending and shotblocking are becoming more predictable and more dynamic.