The Key to Keeping Kevin Durant in Oklahoma City? Russell Westbrook

For the last five years, if not longer, the relationship between Kevin Durant and Russell Westbrook has been the subject of fascination, speculation, discussion and exaltation. Not since Shaquille O'Neal and Kobe Bryant were brought together for a Los Angeles Lakers three-peat have two of the NBA's preeminent talents wound up on the same squad while still on the upswing of their respective careers.

As much as the Shaqobe power couple accomplished on the court, there remains a sense they could've won even more, that they may have left another title or two on the table. O'Neal and Bryant certainly felt that way, if their conversation on the former's podcast over the summer was any indication.

The Oklahoma City Thunder's precocious pairing could go the way of its more successful predecessor next summer. Come July 2016, Durant can take his prodigious talents wherever his heart desires—and wherever there's sufficient cap space for him.

Convincing KD to keep his roots set in the Sooner State will require a group effort on the Thunder's part. But no one player in OKC will be more pivotal to that effort than Westbrook.

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Once upon a time, the partnership between Durant and Westbrook seemed explosive for all the right and wrong reasons. There were rumors of discord between the two, of one stepping on the other's toes. Every side eye, every untoward gesture, every bark from one top dog to the other was picked apart, to either predict a split or suggest that such would be better for the Oklahoma City Thunder.

Those concerns seem to have subsided in recent seasons. For one, they're not kids anymore; Durant turned 27 in late September, Westbrook will be 27 by mid-November.

Durant took home his MVP trophy in 2014. Westbrook was a legit contender for last season's top individual honor. Both sport resumes spotted with All-Star selections, All-NBA nods and scoring titles.

If ever there were professional jealousies between them, Durant and Westbrook have probably buried that hatchet by now. Beyond being grown men, rather than gifted man-children, they've now each had a chance to see what life is (and would be) like without the other. Westbrook's even gone so far as to proclaim Durant "the best player in the world."

Durant was the first to get a taste, when Westbrook went down with a knee injury in the first round of the 2013 playoffs. The Thunder still managed to outlast the Houston Rockets in that series, but there was only so much Durant could do to keep them afloat against the Memphis Grizzlies in the conference semifinals.

And by "only so much," I mean 28.8 points, 10.4 rebounds, 6.3 assists and 2.4 combined blocks and steals in a whopping 45.7 minutes per game.

Westbrook's knee problems continued to plague him during the 2013-14 campaign, leaving Durant to fend for himself. All he did was respond by playing the best ball of his career. During the nearly two months Westbrook missed following his third surgery, Durant exploded for per-game averages of 35 points, 7.5 rebounds and 6.3 assists with absurd shooting splits of .527/.399/.878.

That stretch, during which OKC won 19 of the 26 games Durant played, all but ended the MVP race. But rather than convince him that he could lead the Thunder on his own, the time spent without Westbrook seemed to bolster Durant's appreciation of the 1A to his 1. Durant's mother, Wanda Pratt, aside, Westbrook received the most moving acknowledgement from the Seat Pleasant, Maryland, native during his MVP acceptance speech.

And if Durant didn't cherish Westbrook's contributions before, he almost certainly did during a trying 2014-15 campaign. The reigning MVP missed 55 games on account of three separate operations to fix a foot injury that came a season after Durant carried OKC without Westbrook.

From his spot on the sideline, Durant watched as Westbrook did everything but replace the kitchen sink to keep the Thunder within spitting distance of a playoff spot. Once KD went back under the knife in February, Westbrook went on a rampage to the tune of 31.3 points, 9.9 assists and 8.7 rebounds, with nine triple-doubles and five games of 40 points or more.

Despite his best efforts, Westbrook couldn't quite get the Thunder over the hump. They fell a tiebreaker with the New Orleans Pelicans short of securing the eighth and final spot in the Western Conference playoffs.

What he did do, though, was make Durant even better at his job the few times OKC's dynamic duo played together last season. According to Kirk Goldsberry, writing for the now-defunct Grantland (RIP Grantland), Durant hit 60 percent (72-of-121) of his shots off Westbrook's passes in 2014-15.

"With him, playmaking is easy," Westbrook told Goldsberry. "Just find him and get him shots."

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Nobody does that better than Russ. Now in their eighth season together as teammates, the bond between these two, while not perfectly smooth, is as strong as ever. They've been through the lows of the Thunder's inaugural season in Oklahoma City, the highs of barging into the 2012 NBA Finals and everything in between. 

Durant won't find that sort of familiarity, that brotherhood borne of struggle and success, anywhere else. Nor is he likely find a more talented running-mate outside of OKC. Westbrook is no worse than a top-10 player at this point, and the odds of Durant landing on a roster next summer that features another one, barring a significant salary shakeup, are slim-to-none, as Bleacher Report's Howard Beck discussed with Zach Lowe on their recent podcast.

With Billy Donovan running the show, in place of the deposed Scott Brooks, Durant and Westbrook could see their partnership reach further into the stratosphere. As Bleacher Report's Kevin Ding noted, Donovan has revamped the Thunder's stagnant offense into a more wide-open, free-flowing attack.

"This is Donovan's main goal: to put the players in better position to make their own basketball reads and seize easier opportunities," Ding wrote.

So far, Billy the Kid's new strategy seems to be working just fine for his superstars. In the opener opposite the San Antonio Spurs, Durant debuted with 22 points while Westbrook poured in 33 and 10 rebounds. Two nights later, the former piled up 43 points and 12 rebounds while the latter leapt his way to 48 points, 11 boards and eight assists in a double-overtime victory against the Orlando Magic—the third time in their careers that Westbrook and Durant scored 40 points apiece in the same contest.

The more games like these Westbrook puts up next to his running-mate this season, the more Oklahoma City will win and the closer this team will get to a title. That sort of success will make it difficult for Durant to turn down the opportunity to spend the foreseeable future flying high with his superhero-of-a-sidekick.

This is all assuming that Westbrook wants to stay in OKC for the foreseeable future, too. He'll be a free agent (and a highly sought-after one, at that) in the summer of 2017. In theory, Durant could align his future more closely with Westbrook's by re-upping with the Thunder on a two-year pact with a player option in 2017. That way, Durant could hedge his bets if Westbrook bolts and make himself some more money in the process, as Lowe explained:

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Durant could reenter free agency in the summer of 2017, when the cap will likely jump from about $90 million to $108 million — lifting max-level contracts up with it. Durant by then will have completed 10 seasons, the magic point at which a player’s max contract can soak up 35 percent of the cap — up from 30 percent for players in the prior experience tier.

Add it up, and Durant stands to make something like $35 million to $40 million more going this route, instead of signing a long-term contract at the first chance this summer.

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If this option does, indeed, factor into Durant's thinking, Westbrook's influence on his future could extend well beyond the summer of 2016. It's only fitting, considering how central he's been to Durant's decorated past.

As far as basketball is concerned, what more could Durant ask for than to compete at the highest level with his close friend, who also happens to be one of the best players in the world? And, really, what more could Westbrook want than to do the same?

Josh Martin covers the NBA for Bleacher Report. Follow him on Twitter.

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