To understand how Russell Westbrook emerged as a defensive stopper in the playoff series against the Mavericks, you only need to know the story behind his back-to-back steals in Game 4. You remember those plays, don't you, Thunder fans? I mean, there were a lot of big-time, late-game highlights in that series-clinching victory. James Harden driving to the basket. Kevin Durant draining 3-pointers. Serge Ibaka throwing down big dunks. But those Westbrook steals in the fourth quarter disrupted a Dallas offense that was finding a rhythm and threatening to match Oklahoma City basket for basket. They were the crowning moments in the re-emergence of the defensive dynamo that terrorized college basketball at UCLA and enamored Thunder decision-makers on draft day.