Say you’re a Dallas Mavericks fan, and you left to go live under a rock shortly after the Mavs won their NBA title in June 2011. You emerge from that rock to watch Dallas’ regular season opener against the Los Angeles Lakers on October 30, and you take a look at the roster.

Something tells me the likely reaction would be something along the lines of, “Um, exactly how long was I gone?”

The Mavericks’ radical roster makeover since their championship makes Washington Redskins owner Daniel Snyder’s personnel moves look restrained. In just 16 months, the Mavericks have released all but four players from that championship team. Only two of them — Dirk Nowitzki and Shawn Marion — were regulars. Only six players return from last year’s team, which saw its season end in the first round of the playoffs.

The other four returning players are Rodrigue Beaubois, Dominique Jones, Vince Carter and Brandan Wright. Dallas’ rallying cry after winning the title was “Keep our powder dry.”

At least that’s what owner Mark Cuban kept saying. His desire to save money after the title was tied to luring one or two true superstars to Dallas last summer to surround Nowitzki and to take over the franchise once Nowitzki retired.

Cuban and the Mavericks failed on that front. Deron Williams chose to stay in New Jersey. Dwight Howard, a player some thought the Mavs could trade for, will be in Laker gold in the opener. So will Nowitzki’s former running mate, Steve Nash.

The Mavericks did their best to give Nowitzki as competent a supporting cast as they could this season without mortgaging their financial flexibility. The results are solid. They range from competent professionals like forward Elton Brand and center Chris Kaman to enigmatic youngsters like O.J. Mayo.

The Mavs grabbed big man Eddy Curry late last week to replace suspended guard Delonte West. There are three rookies, including a 28-year-old pivot man who went to Florida State after a stint in the military. It is a motley crew, more so when you consider that Nowitzki will miss the first few weeks of the season due to knee surgery.

Life without Dirk
Is this the start of the inevitable decline and end of the Nowitzki era in Dallas? Or has it already begun? I’ve detailed the decrease in Nowitzki’s overall numbers the past two seasons, but I still believe he has good years left. Good, not great. Even the great ones slow down eventually. That’s why the supporting cast is so critical.

The Mavs tried to cling to the glory days once before. Remember 1991? Entering that season, the Mavericks had a successful but aging core of players, namely Rolando Blackman, Brad Davis and Derek Harper. In an attempt to keep the Mavs relevant, they went after another group of aging veterans — Fat Lever, Alex English and Rodney McCray — as Dallas attempted to build around its young star, Roy Tarpley.

Of course that failed miserably. Tarpley’s drug abuse, combined with the mounting injuries to the older players, precipitated a decade-long spiral for the franchise, one that didn’t end until Cuban bought the team and Nowitzki was in his third NBA season. Is that where this Mavericks team is headed?

When you look at this roster, there’s Nowitzki and a bunch of complementary parts. Now, they might end up working well together, but it’s still a chemistry experiment. Nowitzki’s knee means you can expect a slow start.

The harder part will be finding the younger players around which the Mavs will build their roster once Nowitzki is gone. None of this year’s draft choices — Jared Cunningham, Jae Crowder and Bernard James — look like cornerstone players. They may fill nice roles down the road, but they’re not going to be superstars.

If it sounds gloomy, well, it is. We’re witnessing the slow, inevitable decline of the greatest stretch in Mavericks history. Only time will tell if Cuban will find a formula that will allow the Mavericks to return to the NBA finals one day.