Since the Cavaliers won their first NBA title back on June 19, NBA teams have undergone a number of changes over the long summer offseason. NBA.com's Shaun Powell will evaluate the state of each franchise -- from the team with the worst regular-season record in 2015-16 to the team with the best regular-season record -- during the month of September as we look at 30 Teams in 30 Days. | Complete schedule

Today's team: Dallas Mavericks

2015-16 record: 42-40

Who's gone: C Stanko Barać, F Jeremy Evans, G Raymond Felton, F David Lee, C Zaza Pachulia, F Chandler Parsons, C JaVale McGee

Who's new: C A.J. Hammons (Draft); F Quincy Acy, F Harrison Barnes, G Seth Curry, G Jonathan Gibson (free agency); C Andrew Bogut, C Stanko Barać (trades)

The lowdown: Since winning the 2011 championship, the Mavericks haven't escaped the first round.

But don't feel too bad for Mavericks star Dirk Nowitzki. The future Hall of Famer's career earnings hit $220 million and his pal, Mavs owner Mark Cuban, bumped Dirk's two-year extension to $50 million more this summer. He's the best player in franchise history, is beloved in a football-first city and also has a championship ring. And he'll never pick up a tab in Dallas or Berlin.

We'd all like to be that poor.

Now Nowitzki, 37, is winding down a tremendous career ... even if he's spending his sunset with a team headed sideways. Ever since winning their only championship, the Mavericks have struggled to find firm footing. Many observers thought Nowitzki's championship came in the nick of time, which proved true as that "lone star" team of 2010-11 had maxed out and was quickly dismantled.

That wouldn't be such a bad scenario, except last season, five years after the parade, Nowitzki averaged 18.3 points and was still the best player on the roster.

He said he didn't want to be part of a rebuilding process, but the golden parachute payment from Cuban and the desire to spend his entire career with one franchise (a la Kobe Bryant/Tim Duncan) seemed to pacify Nowitzki. In the meantime, the Mavericks are patching their holes in a frantic attempt to stay competitive, rather than tearing it down and starting over.

That option prevents a team from crashing to the bottom, which means no lottery picks and also tends to keep the salary cap only somewhat flexible. The Mavericks have the symptoms of a team stuck in the dreaded middle, too good to build through the draft, too limited to make a deep playoff run.

Their summer all but guaranteed the status quo. They lost Parsons, Pachulia and Felton to free agency and added near-carbon copies in Barnes, Bogut and Curry. They didn't have a first-round draft pick and no shot at getting Kevin Durant or any other A-list free agent. Their plan: Stay competitive and hope to make a bigger free-agent splash next summer when the cap rises.

The Mavs did benefit from Durant going to the Warriors by snatching up Barnes, the odd man out in Golden State. Dallas hopes the change of scenery brings out the best in Barnes, who was a secondary option with the Warriors. He flopped in the 2016 NBA Finals but that didn't deter the Mavericks from giving Barnes top dollar and ensuring him a prominent role in the rotation.

Is Barnes ready to be a prime-time, 35-minutes-a-game player who can compliment Nowitzki or, even better, replace Dirk as this team's lead singer? In four seasons with the Warriors he averaged 10 points and 4.6 rebounds in 28 minutes. He started for the Warriors over the last two seasons, although that was mainly because coach Steve Kerr wanted Andre Iguodala coming off the bench. Barnes hasn't been a flat-out star since he was the nation's Mr. Basketball in high school but he'll get every chance to prove Dallas right or wrong.

Parsons bolted for the Grizzlies in free agency and Dallas rarely saw the player who looked like a future star in Houston. It's possible the Mavericks made a value signing with Curry. He didn't get minutes in Sacramento until the last few months of the season and played well in an increased role. With the backcourt being somewhat thin, Curry can compete for a sixth man role and play either guard spot.

Two summers ago, the Mavericks thought they had a great chance to return among the contenders. They had a verbal deal with DeAndre Jordan. With him, Parsons, Dirk and Wesley Matthews, along with the leadership of coach Rick Carlisle, there was good reason for optimism. But then Jordan reneged on the deal, Parsons got hurt and Matthews was sub-par in his first season in Dallas.

Dirk continues to defy age, but at some point very soon Dallas must move to the next era. Maybe that's happening now. It's up to Barnes and whomever the Mavericks bring in next.

Coming Next: Memphis Grizzlies

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Veteran NBA writer Shaun Powell has worked for newspapers and other publications for more than 25 years. You can e-mail him here or follow him onTwitter.

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