Mark Cuban isn’t a happy man right now. He attempted an experiment with Rajon Rondo at PG last season, and an epic disaster occurred in the playoffs as a result. This year, the Dallas Mavericks are trying out Deron Williams at the position, but the early results haven’t been too encouraging. He’ll miss the entire preseason with a strained right calf, and he might even be absent for a portion of the regular season too. That isn’t a great sign for this franchise that already has two other starters, Chandler Parsons and Wesley Matthews, set to miss extended time with serious injuries.

Williams still hasn’t gone through a full practice with the Mavericks. Both of his calves are actually injured, because he hurt the left one before training camp opened. You don’t really want your PG to be suffering in both legs as the regular-season opener approaches, but that is the position head coach Rick Carlisle finds his team in.

“He’s doing better, but he will not play in the exhibition games,” Carlisle said to ESPN. “We’ll see if we can get him ready for the opener. It’s been a frustrating thing for him, but we’re making progress. We’ll get there. I just don’t have a timetable.”

This must be a frustrating situation for Dirk Nowitzki, who isn’t exactly a spring chicken anymore either. Williams averaged 13.0 points and 6.6 assists per game last season for the Brooklyn Nets, and he will likely be a nightmare of colossal proportions for the Mavs. It is a shame that Dirk’s final years in the NBA will be on a team with no foreseeable shot at making the playoffs, but at least he has that one championship to hang his hat on. Williams, on the other hand, doesn’t have a whole lot to be proud of in his career, and this might be the PG’s last shot in the league if things don’t go well.

Dave Daniels is a Featured Writer for www.RantSports.com. Follow him on twitter: @AllDave_AllDay, like him on Facebook here or add him to your network on Google.