Some burning questions for the Mavericks second half of the season

The NBA's more than halfway through the season before the All-Star break even hits, but it's always been easier to lump the first and second halves of the season around the four-day break in late February.

With that in mind, here are the most pressing questions, issues and topics concerning the Mavericks when they resume play on Wednesday.

What's going to happen at the trade deadline?

Perhaps the biggest mystery of all is what Mark Cuban, Donnie Nelson and the rest of the Mavericks front office are going to do before Thursday's deadline. Cuban has flipped-flopped, stating the "Bank of Cuban" is open, to saying he doesn't want to make a deal to just make a deal.

I'm sure Cuban wants to improve the team somehow, but in reality, not many teams want what the Mavericks have. Dallas has a few intriguing pieces but don't mistake intriguing for "valuable."

There's a ton of expiring contracts that Dallas can unload on a team looking to get under the luxury tax hit but not much else. There are some interesting names that have been linked to Dallas out there (Samuel Dalembert, Brandon Jennings, Josh Smith, J.J. Reddick) but there are two problems: one, many other teams can beat what Dallas can offer, talent wise.

Two: why make a deal now? A majority of the Mavericks targets (Smith, Jennings, Dalembert, Reddick) will be free agents this summer. The Mavericks aren't going anywhere this season and the players they want to acquire will still most likely be acquirable this summer. There's no reason for Dallas to make a deal when there will be plenty of deals to be made this summer. Unless there's a stone-cold-lock, home-run deal (it'd have to be for an Eric-Gordon type player, I'd imagine), the Mavericks will most likely stand pat.

Is the old Dirk back?

I've pointed out how this year's Dirk just isn't up to snuff with the old, lovable and efficient Dirk we all know. In the last few games, it appears he's returning.

Dirk had two great back-to-back games against Sacramento and Atlanta and they weren't just catch and shoots: there were post ups, spins, off-ball cuts and more. Dirk has even admitted in recent days that up and till now, his health has basically allowed him to be nothing more than a stretch-four, catch and shoot specialist.

We'll know for certain if the old Dirk is back if the free throws ramp up a bit and the paint scores increase. It seems his legs are healthy enough from him to do so.

Which lineup is Carlisle going to stick with?

This is been frustrating for fans, media and watchers alike: Rick Carlisle changing his rotations and lineups on the fly, desperately trying to find something that sticks.

The Dirk-Chris Kaman lineups are just a mess, according to NBA.com, the Bernard James starting lineup had a nice run but is now getting outscored by 5 points per 100 possessions and the (supposed) dream lineup of Darren Collison-O.J. Mayo-Shawn Marion-Dirk-Elton Brand? A whopping net-rating of -28.1.

Many (including myself) have wondered why Carlisle chooses to replace Marion in that last listed lineup with Vince Carter. Carter's contributions have been great for what he's paid and his role on the team but I wondered why taking out your team's best defender made sense. It appears Carlisle and his coaching staff are justified: the lineup of Collison-Mayo-Carter-Dirk-Brand outscores teams by 4.7 points per 100 possessions. A lot of that success has to do with Carter's work on the defensive end being acceptable enough that his offense really shines and pushes this group forward.

That'll be why you'll most likely see that unit close games. The only real question now will be what Carlisle does with the starting lineup.

What to make of Darren Collison?

Collison has had such a strange season. After a nice start, he plummeted in November/December before rebounding with a spectacular January, offensively.

That's the thing: for every great step Collison takes forward, he takes one equally backward. His offense has shined this season and he's gotten ahold of the awful turnovers he was committing around as recent as Christmas time.

In fact, Collison is within distance of joining the elusive "50/40/90 Club." It's when a player posts a field goal percentage of at least 50, three-point percentage of at least 40 and free throws at least 90. Collison right now? He's at 48.5/39.3/90. His efficiency has been great. Or so you think.

You look at those wonderful shooting numbers and the improving passing numbers, but it doesn't add up. When he's on the floor the Mavericks score at a rate of 102.6 points per 100 possessions. Off the floor, that number only dips to 102.4, which is nothing. As great as Collison has been with his shooting and he's steady passing game, it's not making the Mavericks offense that much better or worse. It's a wash.

And that's when the defense comes in. When he's off the floor, the Mavericks defense is 6.9 points per 100 possessions better (106.7 to 99.8). That's a substantial gap and the reasons are numerous: Collison gets pushed around a lot with a smaller frame, gets lost in long-half court sets on D and can't navigate a pick and roll on defense any better than I can navigate myself anywhere outside of Texas.

Team's routinely crush Collison by forcing him in pick and roll situations and having him chase his man off-screens. Any team that features two competent big men destroy Dallas in the half court, because it forces Dirk to guard someone who isn't a stiff. Opponents then run as many pick and rolls against a Dirk/Collison tandem as they can.

Watch the Atlanta tape again: whether Dirk was guarding Al Horford or Josh Smith, the Hawks didn't care, they just continuously ran screen and rolls against him and Collison. Horford and Smith combined for 47 points on 20 of 39 shooting (51.3 percent). Jeff Teague scored 20 points and got seven free throw attempts when he blew past Collison and Dirk.

Obviously, Dirk isn't going anywhere, which makes Collison the expendable piece. Point guard defense is a huge part of the NBA game and Dallas has none of it with Collison. It's hard to create an elite defense when your point guard can't defend the most used play in basketball.

What hurts even more is that teams can kill Collison with pick and rolls even when he isn't guarding them. Watch the Orlando game from a week back: J.J. Reddick got open look after open look when Collison would go brain-dead and fail to help O.J. Mayo out when he got caught in a screen. Collison's awareness on defense just kills the Mavericks. Flat-out kills them.

It's a shame because Collison does so many other things great. But if his offense isn't pushing the needle either way for Dallas and his defense is a giant net-negative, how can you commit to that? I've enjoyed watching a Mavericks point guard be a one-man fastbreak but there's more to the game than that.

Will this be the last time we watch O.J. Mayo as a Maverick?

One of the biggest questions surrounding the off-season for Dallas is what happens with Mayo. He has a player-option for next season around $4 million. It's widely believed that after this season, he'll opt out to earn a much more lucrative and long-term deal.

But will that happen? After a superficial hot-start boosted by unsustainable shooting numbers in October and November, Mayo has come back down to earth. He's still scoring but it's all coming on jumpers -- according to NBA.com, 479 of his shot attempts have been either three pointers or from mid-range.

Aside from shooting the ball better, Mayo's numbers this season are more of a byproduct of his minutes increase than anything. His per 36 numbers are all pretty much even across the board in rebounds, assists, points, turnovers and free throw attempts. His assist numbers are higher but so are his turnover numbers. His PER (16.3) is only a few points higher than his average PER (around 14) from Memphis. Mayo's better in Dallas, but it isn't by as much as everyone tends to think.

His defense is still the same as it was in Memphis -- more than acceptable when playing one on one against a ball handler, disastrous when off the ball.

It's probably the main reason Mayo has been guarding point guards as of late. Carlisle probably wants him locked in against a ball-handler and not have him chasing shooting guards through various ball-screens, where Mayo gets destroyed. Mayo also apparently missed the "keep you head on a swivel" day in 7th grade basketball practice -- he gets abused on backdoor cuts more than any NBA player should.

So if Mayo has only slightly improved from his stay in Memphis, what's the market for him? He's still young (25, will be 26 in November), still athletic and still gifted with a great jumper. He can make those tough isolation shots that a team usually needs in crunch time and defenses ramp up their efforts. But is he worth the so-so defense, the awful turnovers and lack of free throws? I'm not sure. Remember, Mayo was on the market for most of the summer of 2012 before he signed with the Mavericks. If Mayo wanted more money, there was certainly enough time to carve out a deal with another team. Maybe Mayo stays put to avoid another situation like last summer.

Then there's the way Mayo talks about Dallas. In his first press conference, Mayo continually said he's wanted to come to Dallas for a long time. Not for the big-market potential but for the culture created by the front-office and Dirk Nowitzki. Throughout the season, Mayo has owned up to his mistakes and Carlisle keeps telling us that there's no one working harder on his weaknesses in practice than Mayo is day in and day out.

It all adds to the mystery of what Mayo does this off-season. Does Dallas want him? Does he really love Dallas as much as he says he does? Does he think he can get more money elsewhere? Does he even value more money over a good situation? It's hard to tell. Take this next few months to sit back and enjoy the Mayo experience while you can -- turnovers, clutch shots and all.

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