This is NBA team-building as a game of Twister: take a mediocre team and make it great without becoming bad enough to land at the top of the draft or clogging your long-term cap sheet with overpaid veterans. The Rockets and Pacers have pulled it off to varying degrees, and the Blazers are in the thick of it now — with a roster competitive enough to satisfy the “never rebuild” edict of Paul Allen, the team’s über-rich owner, but also one with an asset-rich young core and potential max-level cap room in the summer of 2015.

That is when LaMarcus Aldridge will become an unrestricted free agent, and Portland’s brain trust has worked hard to put a bunch of potential paths in play ahead of that next defining moment in the tortured history of this beloved franchise. At least for now, none of those paths involves trading Aldridge early, and none has ever involved a complete Sixers-style teardown — a path several rival executives who are pessimistic about the ceiling of an Aldridge–Nicolas Batum–Damian Lillard core would suggest the Blazers embark upon yesterday.

“Paul Allen has never wanted to rebuild,” says Neil Olshey, Portland’s GM. “He does not want to take three steps backward in order to take four steps forward. So we decided we were just going to have one foot in, and one foot out.”

The foot in: acquiring quality veterans to revamp one of the worst benches in recent league history, a must to chase one of the last two playoff spots in a loaded Western Conference. The foot out: making sure none of those veterans eats into that 2015 cap space, adding two high-upside top-10 picks in C.J. McCollum (Portland’s own pick) and Thomas Robinson (the spoils of Houston’s pre–Dwight Howard salary shedding), and making all these moves without sacrificing a first-round pick or highly valued prospect.

It has been an artful bit of roster-building, opening up several possible long-term routes to 55 wins — the rough benchmark of title contention:

• The current core becomes so good that Aldridge is content to stay and the Blazers use their status as a hot commodity to lure the “missing piece” free agent — Marc Gasol? Roy Hibbert? Brook Lopez? — with that 2015 cap room. Even Olshey admits this is a very optimistic scenario, requiring at least one of the team’s young wild cards to “pop,” as he puts it. “If you take our core and then have one of the young guys pop,” Olshey says, “and you add in that amount of cap room, then you can do a lot.”

• The current core is insufficient, but the younger “upside” pieces are intriguing enough to combine into a trade package for a franchise-level star who becomes available via trade — similar to how Kevin Garnett and James Harden ended up in Boston and Houston, respectively.

It’s unclear if this is feasible, since Lillard is presumably untouchable, and it’s hard to see Portland putting together a superstar-drawing trade basket without including Lillard; the Blazers already owe a first-round pick to Charlotte, and they’ve coughed up five second-rounders in their recent trading binge.

The difficulty of finding that second path highlights the negative scenarios that lurk around these rosy ones — the loss of Aldridge in free agency or via a white-flag trade, and with or without Aldridge, the possibility that the team’s current core won’t ever be good enough to get Portland off the treadmill of mediocrity. “Something like 45 wins is OK with a young roster, starting a bunch of rookie scale guys, and when you have all this cap room in 2015,” Olshey says. “But if you’re capped out with no flexibility, hovering around 45 wins? That’s not acceptable.”

The core Blazers aren’t all that young anymore. Aldridge just turned 28. Batum is almost 25, and Lillard is a relatively “old” second-year star at 23. Shooting guard Wesley Matthews is almost 27. If all these guys are so intriguing, why haven’t they won more games together? Keeping Aldridge happy and moving forward requires getting better this season, and one question will determine whether the Blazers manage that: Can this team guard anyone?

The Blazers were a disaster defensively last season — 27th in points allowed per possession, playing J.J. Hickson at center (we’ll be telling our grandkids about that someday), and using a scheme that just didn’t work. Terry Stotts, the team’s head coach, imported that scheme from Dallas, where he was an assistant on the 2011 champs, and stuck with it in part as a crisis response to playing the undersize Hickson so many minutes.

Stotts has scrapped that scheme and will unveil a more conservative one this season, he says, and the Blazers are banking on both depth and experience to improve their defense. Lillard was a train wreck defensively for most of last season, struggling to read NBA offenses and get through screens both on and off the ball. That’s typical for rookies. “He’s a proud young man,” Stotts says of Lillard. “He’s been getting hit hard all offseason about his defense. He wants to show he can do it at both ends.”

Robin Lopez, acquired almost for free as part of the Pelicans’ sign-and-trade for Tyreke Evans, is a giant human being who tries hard and provides at least some rim protection — “some” being much better than the “none” Portland had last season. Only Milwaukee allowed more shots per game at the rim, and Portland games sometimes regressed into sad dunkfests, especially when the Blazers basically gave up amid injuries and losses over the last month of the season.

Added depth carries other benefits, Stotts and other Portland higher-ups say. Guys can play both ends of the floor harder, knowing Stotts will feel safe resting them when they get tired. The team might be able to improve its transition defense by sending fewer players to the offensive glass, since the starters, backed by capable NBA reserves, won’t feel an urgent need to score on every stinking possession this season. Stotts can pull guys who blow assignments without worrying about tossing an unqualified substitute onto the floor.

And players can challenge shots more aggressively at the basket, since foul trouble to starters will no longer amount to a death sentence. Only four teams fouled less often per shot attempt than Portland last season, and while not fouling is generally a good thing, Stotts believes the Blazers were almost too cautious in this regard. “Not fouling can be a double-edged sword,” he says. “I thought we laid off on a lot of plays last season. There were possessions where we could have taken a foul or contested a shot, but we didn’t, because we were too worried about fouling.”

He’s right. Hickson, at 6-foot-9, is too small to protect the rim, and usually a step behind in realizing where he needs to be. Aldridge’s regression last season was more surprising. He was inconsistent in executing Stotts’s scheme against the pick-and-roll, and his typical rim-protection technique amounted to politely waving at an opposing player mid-dunk. He can be much better, and he’ll have to be if Portland wants any hope of snagging one of those last two playoff spots.

Last season, the Blazers attacked pick-and-rolls more aggressively than any non-Heat team. They would have the big men guarding screeners lunge out at opposing point guards, seeking to cut them off high on the floor. Playing that way amounts to temporarily double-teaming the ball and leaving three defenders to guard four players below the 3-point line. It’s a high-risk strategy. If that point guard can either dribble or pass through those first two defenders, the defense is toast.

Portland’s issues started at the top, where Hickson and Aldridge (not to mention the typical rookie struggles of Meyers Leonard) just couldn’t time their lunges in a way that really interfered with opposing point guards. Jameer Nelson isn’t exactly the quickest point guard in the league, and he’s about to turn the corner on this pick-and-roll with Nik Vucevic in part because Hickson is too late leaping out to contain the ball:

And once a point guard turns the corner into the lane, ahead of two defenders, it’s over. Aldridge steps up to contain Nelson’s drive, and Nelson slips an easy bounce back to Aldridge’s man (Gustavo “Fring” Ayon) for a layup:

No team in the league struggled more against pick-and-rolls on the side of the floor. Big guys would screen for point guards who would dribble up toward midcourt, draw two defenders, and flick a simple pass to the screener wide-open along the baseline. When Darren Collison can hit Dirk Nowitzki on a pick-and-pop this open, you’re in trouble:

Help defenders had to scramble like mad on these plays, since you can’t just let Nowitzki types line up jumpers or dribble unmolested to the hoop. That’s why Aldridge is rushing from the paint out toward Garnett on this Courtney Lee–KG pick-and-pop on the left side:

Problem: No one on the right side of the floor is aware they need to pick up Aldridge’s original man, Brandon Bass, and Garnett is about to hit Bass for an easy bucket in the lane.

The same general thing is happening here, as Marc Gasol has just caught a pass from Tayshaun Prince during a pick-and-pop on the left side:

Portland’s actually doing well enough here. Joel Freeland, Gasol’s original guy, is scrambling back toward Big Spain. Hickson has slid off of Zach Randolph (no. 50, near the rim) to prevent Gasol from walking in for a dunk. Matthews (no. 2, on the right wing) has darted into the passing lane from Gasol to Randolph, cutting off that possibility. But Lillard, guarding Mike Conley (no. 11, up top), hasn’t realized he has to now pay some attention to Matthews’s man, Tony Allen (no. 9), who finished this play by cutting into the lane, catching a pass from Gasol, and laying the ball in.

Even when Portland executed 80 percent of its defense correctly, it still failed. Playing this way required an on-a-string cohesion these guys just didn’t have. Inexperience accounted for some of that; NBA defense is hard stuff, and in Lillard, Leonard, Freeland, Will Barton, and others, the Blazers gave minutes to a lot of guys who had played almost none of it.

But some of the failure stems from the lack of a standout defender on the roster. Aldridge has been solid, and often better, but he was not there last season. Matthews might be the team’s best defender; he’s feisty, smart, and hyper-alert, but he can only do so much with his God-given size and athleticism. Batum looks the part, but even his fans within the organization would admit he’s become overrated on that end. He has the speed and length to guard multiple positions, and he has put it all together for occasional stirring stretches of defense and highlight chase-down blocks.

But there’s no real evidence Batum is a consistently good NBA defender — yet. The Blazers have been stingier with Batum on the bench for nearly his entire career, per NBA.com and Basketball Value; his head-to-head counterparts have always produced well; and the more complex public databases have never been kind to him. Batum has the tools and brains, but he too often lets his attention wander in a particular direction for a beat too long. He’s a frequent victim of backdoor cuts, and he lacks the quickness to defend elite ball handlers for long stretches.

Again, Batum’s not bad — he’s just not the stopper he looks like he should be. He’s closer to average, which is fine. It’s just hard to build an effective NBA defense around a bunch of average (or worse) defenders playing a shaky scheme, and building an effective NBA defense is basically Step 1 to becoming a serious NBA team with staying power.

The Blazers don’t have aspirations of being an elite defense next season. If they can get to somewhere around league-average and combine that with a top-eight offense, they’ll have a good shot at making the playoffs. And the ingredients for a very strong offense are here. They scored 106.4 points per 100 possessions when Aldridge, Lillard, Batum, and Matthews shared the floor together, about equivalent to Houston’s no. 6 overall mark last season, per NBA.com. And Portland had the best offense in the league for a 15-game stretch that started with Eric Maynor’s arrival via trade and ended when the season went into total free fall. That’s a small sample size, but it has raised hope internally that Portland can achieve the “elite offense/average defense” profile it will take for them to make the playoffs. “People always say that defense wins championships,” Stotts says. “But you know what? Offense and defense win you the title. You can win a lot of games with a great offense.”

Lillard is a major weapon, off the dribble and as a spot-up player. Aldridge is a beast, even if he’s gotten too jumper-happy of late. Batum took nicely to Stotts’s “flow” offense, emerging as a wily secondary playmaker and blowing away his career assist numbers. He was scoring more before a midseason wrist injury, and the organization still hopes Batum has at least a mini-leap left in him. “Nic is our swing guy,” Olshey says.

The team embraced the 3-point shot, and they’ve added several guys who can fire away in Mo Williams, Dorell Wright, McCollum, and Allen Crabbe. Wright in particular should serve a key role as a small-ball power forward off the bench; he’s a very good outside shooter who can facilitate a bit on offense, and Portland has always played well in smaller groups featuring Aldridge at center.

Stotts will help by reinventing the team’s defense, he says. He’ll scrap the hard-charging style against pick-and-rolls, replacing it with a more conservative base in which the big man guarding the screener will hang back in the lane. The Blazers will try to keep side pick-and-rolls on one side of the floor instead of chasing a point guard toward the middle, and they’ll have their bigs deal with pick-and-rolls in the middle like this much more often, Stotts says:

That strategy will concede the occasional midrange jumper — look how open Steve Nash is in the above photo — but Stotts will take that kind of shot over the endless reel of dunks Portland gave up last season. It’s a style that also fits well with Lopez, a smart but plodding defender who gets into trouble when he scurries too far from the rim.

If all the changes don’t work very well, Portland will have a tough time making the playoffs. In the last 10 years, only 32 teams have made the postseason while ranking 16th or worse in points allowed per possession. Most of those teams — 20 of 32 — compensated with a top-five offense, and 25 of 32 sported top-10 overall offenses. The seven exceptions — the teams that made the playoffs despite being mediocre or worse on both ends — all played in the Eastern Conference during its prolonged nadir. In other words: If you want to make the playoffs in the West with a so-so defense, you better actually have a so-so defense (and not a plain bad one), and you better score the hell out of the ball on offense.

Portland knows how tough this task is going to be, which is why it will keep all its options open if the season proceeds poorly. The easy suggestion in the event of stagnation would be to trade Aldridge a year before his pending free agency becomes a crisis, as Utah did with Deron Williams. But that will be tricky. Allen’s aversion to rebuilding is real, and some of the asset-rich teams that would make for natural Aldridge trade partners aren’t trying to win this season. Aldridge is too good for a Jrue Holiday–style deal that brings only future picks. The Blazers also lack a bad salary they’d be anxious to dump, making the construction of mega-offers less palatable.

Chicago and Cleveland will always be there as potential Aldridge trade partners. The Bulls’ package of Carlos Boozer and some combination of Jimmy Butler, Nikola Mirotic, and the first-round pick Charlotte owes Chicago is the most obvious Aldridge trade package in the league, though a Portland-Chicago deal isn’t as simple as it looks. The Cavs have three potentially tradable young guys (Dion Waiters, Tristan Thompson, Anthony Bennett), three extra future first-round picks, and a clear goal of chasing a playoff spot this season after three years of misery and ridiculous lottery celebrations.

But the Blazers keep emphatically swatting away the Aldridge thing, as if it’s silly to even ask. “It’s not on our mind,” Olshey says, “and it’s not on his, either. LaMarcus just wants to win. He wants to win tomorrow night. He doesn’t want to hear about having cap room two years from now.”

They might be playing possum to maintain their leverage, but the Blazers don’t seem urgently concerned about finding an Aldridge solution with two years remaining on his contract. And that raises the other Portland trade possibility: What if they could deal for a long-term solution at center, someone better than Lopez, without trading Aldridge?

The obvious candidate is Omer Asik, semi-expendable in Houston, but the Blazers don’t have much to offer the Rockets. That would shift the focus to guys like DeAndre Jordan and JaVale McGee — big-money youngsters with fitful developmental curves whose teams might seek a more stable presence in Lopez, provided the Blazers sweeten things by including Robinson or McCollum.

None of these deals is likely; no specific trade ever is. But there’s a decent chance the current roster just won’t defend or rebound well enough for Portland to proceed along the preferred path of keeping Aldridge happy, making the playoffs this season, and building up to something bigger. It may be that Portland has built itself a core with a ceiling lower than we’d expect given the starry names and droolworthy skill sets — a core that needs a major long-term jolt from free agency or the internal development of a very young player other than Lillard. Those things may never happen. It’s an uncomfortable possibility to contemplate, but it’s one Olshey and his staff are ready to address head-on. And they’ve smartly put themselves in position to respond in a variety of ways to just about any possible trends that emerge with this roster. Portland is a franchise to watch.