Will they stay or will they go?

The only certainty about the upcoming summer for the Mavs is that it'll be interesting.

Owner Mark Cuban, as usual, plans to be "opportunistic." In this case, that means swinging for the fences in what might be the best free agent market in NBA history. Even if the Mavs strike out in their quest for another superstar, there could be significant tweaking of the roster.

Here, as a complement to Jeff Caplan's report card for the Mavs' 2009-10 season, is a look at how likely it is that each player on last season's roster will return:

Dirk Nowitzki – 95 percent

I thought this was a lock until I heard Dirk’s comments after the Mavs’ third first-round exit in four seasons, which he didn’t back off the following day. Can you blame a superstar in his situation for considering his options? However, it’d still be stunning if Dirk decides to leave Dallas this summer. My hunch is he’ll simply decide not to opt out of the final season of his contract, keeping his options open if the Mavs aren’t any closer to a title a year from now.

Jason Kidd – 99.9 percent

The Mavs love him despite disappointing performances in the playoffs the last three seasons. They won’t shop him. Even if they did, there wouldn’t be much, if any, interest in a 37-year-old with two seasons remaining on his contract. The Mavs need Rodrigue Beaubois to develop his point guard skills this summer enough to let them manage Kidd’s minutes.

Shawn Marion – 99.9 percent

Teams aren’t looking to trade for a 32-year-old forward who relies on athleticism and is under contract for four more years, even though Marion doesn’t make a ton of money by NBA standards. It’ll be interesting to see how Marion’s role change if Beaubois and Caron Butler also remain Mavericks. A lot of Roddy B’s minutes might come at Marion’s expense.

Caron Butler – 50 percent

Does Butler fit that well with the Mavs? He’s a natural small forward who starts at shooting guard in Dallas, where he was inconsistent with flashes of brilliance. You can count on Butler’s name coming up in trade talks this summer, especially if the Mavs get in serious discussions about a sign-and-trade deal for a superstar. Butler’s talent and expiring contract ($10.8 million salary) make him an attractive trade chip. The Mavs knew that when they made the deal with Washington to bring Butler to Dallas.

Erick Dampier – 40 percent

There is no way that Dampier will finish his current contract, either in Dallas or elsewhere. He’s not worth paying a $13.1 million salary. Due to some creative language in the contract, that money is totally nonguaranteed and the Mavs can use him as an instantly expiring contract in their trade talks. That’s an extremely attractive asset to cost-conscious teams. But Dampier might not be done in Dallas. Whenever he’s released, whether it’s by the Mavs or another team, the Mavs will likely be interested in bringing him back. Just at a fraction of what they’ve been paying him.

Jason Terry – 80 percent

The emergence of Roddy Beaubois will cut into Terry’s role. Terry’s contract is no longer totally untradeable, as only about half of his 2011-12 salary is guaranteed, pending certain incentives. But the odds are he’ll be back for at least one more season. If that’s the case, the question is whether he’ll still be the first guard off the bench.

J.J. Barea – 60 percent

Barea gets asked about a lot when the Mavs are talking trade. That’s because he’s a proven contributor at a discount price ($1.7 million team option for next season). It wouldn’t be surprising if Barea gets thrown in a blockbuster deal this summer, especially with the Mavs’ plan to prepare Beaubois to be the backup point guard.

Brendan Haywood – 60 percent

The Mavs’ brass made it very clear when they blockbuster deal with Washington went down that they wanted to keep Haywood for the long haul. The Dallas decision-makers might not be as excited about Haywood as their big man of the future after his up-and-down few months as a Mav. But what better options are out there? Haywood is an unrestricted free agent, but it’ll be tough for him to find more money and a better fit than the Mavs can offer.

Rodrigue Beaubois – 95 percent

How could Roddy B’s return not be a lock? Because if the Mavs hit a home run in the sign-and-trade market, Beaubois will probably have to be part of the outgoing package. Think of it as a win-win situation: His departure would mean the Mavs are adding a superstar; his return would means the Mavs have a potential star in the making.

Eduardo Najera – 90 percent

The next two seasons on Najera’s contract aren’t fully guaranteed, but the savings aren’t significant if the Mavs decide to get rid of him. Plus, they need Najera’s nastiness, even if he doesn’t play many minutes. He’s a good teammate who opponents hate. In other words, he’s the kind of guy you want on the fringe of the rotation.

DeShawn Stevenson – 95 percent

He’d be crazy not to pick up his player option for $4.2 million next season. It’s possible that he could then be flipped to another team in a trade, since he is an expiring contract. It’s more likely that he’ll continue in his role as a rarely used defensive stopper and be dangled as an expiring contract around the trade deadline.

Matt Carroll – 99.9 percent

The Mavs aren’t holding their breath for other teams to show interest in a player who scored 46 points last season and is owed $14.4 million over the next three seasons.