The problem is there might not be enough talent around him to keep him healthy. Rick Carlisle is doing his best to limit everyone's minutes to keep them fresh for the playoffs. After dropping three straight and sliding to 6th place in the west you begin to wonder if the team has what it takes to make it back to the finals. Dirk Nowitzki left the game vs Memphis early with a "tight back".
Part of the health issues may lie with the lack of supporting cast around him requiring Dirk to carry most of the load offensively. Another might be with the absence of Lamar Odom (personal reasons) and Delonte West (finger), or the ineffectiveness of Ian Mahinmi a player who showed a lot of promise early but has faded as the season progressed. Other players such as Brendan Haywood and Roddy Beaubois have been up and down with their performance. Haywood's production in the middle is key to the Mavs with the departure of Tyson Chandler. Haywood has always been capable with more than enough talent to be a productive big, but it doesn't always show. Brandan Wright and Yi Jianlian have been pleasant surprises off the bench but not big time performers, and Brian Cardinal provides his custodial duties.
Dallas does boast one of the NBA's best benches so the real problem may lie with key players Jason Kidd, Shawn Marion, Vince Carter, and 6th man Jason Terry. Vince Carter has been solid as the starting 2 guard. Shooting the three pointer very well and providing nice post game work on smaller guards. However, he tends to disappear in the second half of games at times. It might be conditioning or lack of playing time in the 4th quarter with Jet getting the bulk of those minutes.
Shawn Marion has been the man on the defensive end of the floor, but on the offensive end his offensive game is no where to be found far to often. He needs to produce offensively to provide some relief to Dirk and Jet down the stretch. His offensive in the post and his floaters are plenty effective to provide more offensive output.
Jason Kidd is under a strict minute cap that Rick Carlisle is monitoring very closely. However he has been a dreadful shooter for most of this season. Not to mention almost all of his shots come from behind the arc. He is going to need to become more of a threat in the post and driving to the hoop the rest of the year. He still provides his smarts and passing abilities night in and night out.
Jason Terry has had his struggles shooting on the road, but his scoring this year is his lowest PPG since he joined the Mavericks in 2004. He is still a clutch performer and one of the best the Mavericks have ever had, but teams are finding a way to defend him a lot better. He likes to spot up shoot, shoot off the dribble going right, and shoot floaters in the lane. It seems that he may need to add something to the offensive arsenal.
The Mavericks have enough talent, but a lot of things are going to have to go right for them to repeat as champions. A lot like last year when the team gelled at the right time. Without a healthy Dirk Nowitzki forget it; No player means more to his team.