As discussions between the Houston Rockets and the Oklahoma City Thunder on a blockbuster deal for Russell Westbrook grew serious Thursday, Daryl Morey, Houston's general manager, called James Harden to discuss how both stars might work together. Harden gently cut Morey off and reminded him: "I know how to play with Russ and he knows how to play with me," Morey recounted to ESPN.com late Thursday in Las Vegas.

They played together for three seasons, two of the three foundational superstars who drove the Thunder to the 2012 Finals. Harden was 22 when LeBron James and the Miami Heat overwhelmed Oklahoma City in that series. Westbrook and Kevin Durant were 23. They were one of the youngest teams ever to advance so far. They looked like a dynasty in the making.

Harden never played another game for Oklahoma City. The Thunder traded him to the Rockets in October 2012, in a deal that has proved to be a pivotal moment in NBA history. The trade did not kill Oklahoma City. The Thunder never reached the Finals again, but they made legitimate runs in 2013, 2014 and 2016. Injuries derailed the first two -- two more "what-ifs."

The 73-win Warriors rallied from a 3-1 deficit against Oklahoma City in 2016, an all-time gut punch. The Thunder didn't just beat Golden State in Games 3 and 4 of that series. They overwhelmed them with size and speed and athleticism. They made the Warriors look helpless. They became the team Sam Presti, its architect, envisioned -- the team the rest of the league feared they might become.

And the Warriors summoned something more, because the Warriors are champions (even if they were not champions at the end of that season). Klay Thompson's 11 3-pointers in Game 6 to save Golden State's season literally changed the entire landscape of the league for the next half-decade. The history of the NBA in the 2010s is perhaps more closely interwoven with the history of the Thunder than it is with any other team -- even if the Thunder never won the championship in the Westbrook era.

If you have to boil that history down to two moments, they are the Harden trade and that fateful Game 6. The first cost Oklahoma City a player who has finished in the top-five in MVP voting five times since. The second might have cost them a title, and a chance to keep Durant.

Harden became a different sort of player in Houston, and has shape-shifted since into something we have never quite seen. Westbrook became a very different player when Durant left him as the only remaining star in Oklahoma City. They are probably the two most ball-dominant players in the NBA. They have recorded the two highest single-season usage rates in NBA history: Westbrook in 2017, Harden in 2019. They were the top-two finishers in one of the most contentious MVP races ever, and one of the delightful subplots of this strange, fascinating trade will be watching die-hard Houston fans grapple with accepting the star they derided as an unjust MVP usurper.

In their years apart, Westbrook and Harden have developed such singularly relentless, controlling styles that it is hard to imagine them playing any other way. It is almost hard to remember how they meshed seven and eight seasons ago. Houston is betting the two stars can remember -- that they can ease back into old habits, and blend what they are now with what they once were together.

That was Harden's message to Morey over the phone on Thursday. That was Westbrook's message in choosing the Rockets as one of his destinations -- along with the Miami Heat, who may now pursue Paul as something of a consolation prize. (The Rockets hoped to turn the deal into a three-team trade, according to ESPN's Adrian Wojnarowski. That they could not do so suggests Presti might feel he can wring more for Paul by doing that deal on his own. Trading Paul could also deflate Oklahoma City's win total, and vault the Thunder higher in the 2020 draft. An under-the-radar loser here: Atlanta, who owns Oklahoma City's lottery-protected 2022 first-round pick. The Thunder are starting a deep rebuild. If that pick falls in the lottery, the Hawks get two second-rounders instead.)

Westbrook was enthusiastic about playing with Harden again, per sources familiar with the talks. That kind of buy-in matters. Both superstars will have to change for this to work, even though Mike D'Antoni will probably stagger minutes as rigidly as he did with Harden and Paul. D'Antoni's experience coaching Westbrook on Team USA boosted Houston's comfort level making this deal, sources say. The Thunder belonged to Westbrook in almost every way. The Rockets do not. Maybe that alone will spur some change in him.

The Harden-Paul combination worked so well in part because Paul is lethal on catch-and-shoot 3s. Westbrook is not. Westbrook has hit about 33% of such shots combined over the past three seasons, per NBA.com. He is one of the worst high-volume 3-point shooters in NBA history.

He has, frankly, been useless away from the ball, save for the occasional slash inside for an offensive rebound. (Steven Adams is maybe the biggest winner in this deal, by the way. He can actually grab some defensive rebounds now. He is one of the league's burliest rebounders, and yet his career defensive rebounding rate is almost on par with that of Andrea Bargnani -- one of the worst big man rebounders ever.)

Westbrook rarely cuts when someone else has the controls. He did enjoy cutting baseline for dunks out of one scripted action centered around Durant, but that set left with Durant. He mostly chills well beyond the 3-point line, hands on knees.

Defenders have learned to ignore Westbrook when he goes into passive off-ball mode. That will now amount to a double-team on Harden. Depending on how much time remains on the shot clock, clogging the paint could short-circuit Houston's offense.

There is an obvious solution: Give the ball to Westbrook a lot! Harden is a much better shooter than Westbrook. He draws more attention away from the ball. He can rest more while Westbrook runs the show. He will get more catch-and-shoot 3s, and he attempted only 70 of them among 1,028 3-pointers last season, per NBA.com. The Rockets might generate more easy fast-break buckets with Westbrook rebounding and sprinting the ball up the floor like a madman.

None of this is unfamiliar to Harden. He just spent two seasons sharing the offense with another of the league's most ball-dominant players in Paul -- a classic, old-school puppet-master point guard. Their partnership appeared uneasy at times. A bit awkward. Harden is not exactly an active-ball cutter. But the Paul-Harden duet got Houston within a whisker of the 2018 Finals, where they would likely have been heavy favorites against LeBron's last Cleveland team.

Westbrook's shaky jumper makes this partnership a little more complicated. Harden might have to cede more ballhandling duty to Westbrook when they share the floor than he did with Paul. The Rockets know that. They are excited to see what Westbrook can do running pick-and-rolls with Clint Capela and three capable shooters -- Harden, P.J. Tucker and Eric Gordon in Houston's projected starting lineup -- flanking them. The floor will open up even more when Houston goes to its Tuckwagon lineup, with Tucker at center over Capela.

Westbrook rarely enjoyed that kind of pristine spacing in Oklahoma City. There was always at least one other player -- a bricky wing, a paint-bound power forward -- cramping space for Westbrook and Adams. For all his flaws and apparent decline over the past two seasons, Westbrook is still a monster athlete. He gets from the arc to the rim faster than almost anyone. When defenders duck under picks -- a common tactic against Westbrook -- he can sometimes put his head down and beat them to the other side of that screen anyway. Dealing with Westbrook takes a mental and physical toll. He is always coming at you. Always. It wears.

When Westbrook did get chances to run a real spread pick-and-roll in Oklahoma City, defenses had few answers beyond hoping someone would miss an open kickout 3.

Of course, getting to that look a little more involves shifting the ball from Harden's hands into Westbrook's. Harden is better with the ball than Westbrook. It isn't close, or at least it hasn't been for years now. Harden has been more efficient in pick-and-rolls, isolations, even in transition. Taking the ball from one player and giving to a worse player is generally a bad idea.

But Houston is hoping it is more imperfect solution than bad idea. They will do it only so much, anyway. Dealing to pair Westbrook and Harden is a wager that they are still malleable after years of getting to do whatever they have wanted. The Rockets will need Westbrook to cut when Harden has the ball; to run into Harden's kickout passes, catch them at full speed, and zip by defenders who had planted themselves in the paint; to rediscover his transition efficiency; to screen for Harden, and vice versa, when matchups call for it.

Harden has to do all the above, too. They both have to recommit to defense.

Westbrook is three and a half years younger than Paul. At bottom, this is a talent play by Houston. During Harden's championship window, the Rockets approach one-for-one trades with a very simple calculus: Are we getting the better player right now? Most statistics suggest they are, even if the current per-minute gap is pretty small -- too small to justify coughing up two picks and two pick swaps when there was not much of a market for Westbrook. Age suggests the gap will widen during the life of Westbrook's contract, which runs one year longer than Paul's. The Rockets are also betting Westbrook's deal will be easier to trade if it comes to that.

The thinking goes that as Paul ages, his superior fit next to Harden won't matter as much as Westbrook's superior talent -- and that Westbrook and Harden will iron out at least some of those fit issues.

The price is really the issue. Most rebuilding teams with holes at point guard -- or just lots of holes -- expressed little interest in giving up any real assets for Westbrook, sources say. That might have changed by Dec. 15, when most free agents signed this week become trade-eligible again -- and by which point some team will feel more desperate than it does today. But given the initial cool response to Westbrook's availability, the Thunder were correct to pounce early. (I have said many times I would not have given up any real assets for Westbrook. The Heat trading Goran Dragic and blah contracts for him seemed like a fair endgame. The market was indeed cool. But remember the old NBA adage: It only takes one.)

They were not going to send him to some woebegone destination. They could not treat the MVP who stayed that way. That left Miami and Houston. It is unclear if Miami was a serious-enough suitor for Houston to give up all of these draft assets.

The Heat don't have a lot of those left to trade, and that complicated talks for Westbrook. They might have been reluctant to deal Bam Adebayo or Justise Winslow; with one or both gone, who would Westbrook and Jimmy Butler play with long-term?

Miami already owes two first-rounders (their 2021 pick, and a protected 2023 pick) to Oklahoma City, a dynamic that complicated trade possibilities. Would the Thunder trade Miami a player who might improve the Heat -- and thus devalue the picks Miami has to send the Thunder?

But there were ways around that constraint. The Thunder could have pushed Miami to lift protections on the 2023 pick. They could have traded both back to Miami and pushed for some or all of the Heat's 2022, 2024 and 2026 picks. Extending the obligation to 2024 and later would have delayed the transfer of those picks well beyond the primes of Westbrook and Jimmy Butler -- in other words, into a future with a higher chance of the Heat being bad. The 2022 draft might be the long-awaited super draft, with both high school players and the last group of one-and-done stars. A good team's future picks have more trade value than its present-day picks.

This kind of push-and-pull infected talks between Houston and Oklahoma City on Thursday. (Talks between the Heat and Thunder had quieted by then, sources say.) The Rockets tried to coax Oklahoma City into taking Houston's 2020 first-rounder, sources say. Oklahoma City refused, and pushed for picks further out. Houston relented, and the two settled on Houston's 2024 and 2026 picks -- both with just top-four protection.

Those protections are light. Harden will turn 35 in 2024. There is more risk here for Houston than would appear warranted. But this is the summer of risk -- of teams sensing a Warriors-free window, and going all-in.

The Rockets can probably talk themselves into this by arguing that shedding Paul would have cost them one first-round pick. The other pick (plus the swaps) is the cost of the talent gap, now and over the next three seasons. Tilman Fertitta wanted a flashy shake-up. He got one.

This is inarguably great return for Oklahoma City. The Thunder have received seven future first-round picks combined in deals sending out Westbrook and George. They have received so many future first-round picks, it will be interesting to see if they can even roster all of them. (They probably don't intend to; teams generally accumulate picks like this to package at least a couple of them in trades.). They have received so many first-round picks, you almost forget they also got Shai Gilgeous-Alexander -- a long-armed menace with All-Star potential.

The once-in-a-lifetime event of Kawhi Leonard holding the Clippers up against a ticking clock gave Presti leverage to turn George into an instant rebuild. This deal is the coda. It's cliched to say the teardown is the easy part, and the buildup is the hard part. That is mostly true. But Presti nailed this teardown to an extent rarely seen.

For Houston, I'm not sure this deal ups their 2020 title chances as much as they hope -- or much at all -- unless the chemistry issues between Harden and Paul were intractable. The Rockets have downplayed those issues publicly and privately, and continued to in the wake of the Westbrook deal. That is what teams do. Capela sent Paul off with a moving Twitter tribute.

But if those issues were real to the point of dividing a potential title contender, the Rockets had to do something. The burden is on both Westbrook and Harden to prove that this trade was better for Houston's 2020 title odds than standing pat would have been.