It seemed more like an inevitability than a possibility when news about the status of Dirk Nowitzki’s knee broke out earlier in the preseason. There was swelling in his knee, and the German hinted at the possibility of surgery if the condition did not improve. Unfortunately, the swelling continued, forcing Nowitzki to undergo arthroscopic knee surgery on Friday. The procedure will sideline him for about six weeks. Chris Bernucca has the details of the situation. Playing without the heart of the team