In choosing Doc Rivers, the Sixers throw the last lifeline to Ben Simmons and Joel Embiid | David Murphy

Doc Rivers is the kind of guy you hope is sitting next to you on the plane when the turbulence strikes. He exudes a brand of certainty that immediately captures your trust.

Part of it is the figure he cuts, and part of it is the way in which he cuts it. He carries his broad ex-athlete’s frame in a weathered sort of way that says he has accomplished much and seen plenty too. Anybody who has spent any time around the longtime head coach should find it difficult to imagine his walking into a room with Josh Harris and walking out with anything less than what he wants.

Clarity. That’s what the Sixers have acquired in bringing Rivers aboard to steady their leaking ship. It might not arrive right away. But by the end of his tenure, they will have it.

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They will know who Joel Embiid is. They will know what Ben Simmons can become. They will know whether those two entities can coexist on a championship team. They will know whether the roster they have assembled is as flawed as it seems. There will be no more excuses.

This is the appeal of Rivers, who has reportedly agreed to a five-year contract after meeting with the organization’s top decision-makers Wednesday in Philadelphia. He carries with him a level of professional capital that neither Ty Lue nor Mike D’Antoni can match.

With their other two finalists, the Sixers faced the risk of ending up back where they started, wondering whether the hubcaps rolling down the highway are the fault of the bus or the driver. If things don’t get better under Rivers, it will be safe to conclude that the problem was never the coach.

That doesn’t necessarily make him the best choice for the current job. There are legitimate reasons to question whether hiring Rivers is the kind of move that a championship organization makes, starting with the fact that he was available to be hired in the first place.

Like Brett Brown, Rivers did not win a championship this season. And, like Brown, he did not do this despite coaching a team that entered the season as one of a handful of favorites to contend for one.

But, then, the Sixers are not a championship organization. That’s one of the few things they have proven over the last five years. Rather, they are an organization in desperate need of a voice that can be trusted, of an authority figure with the ability to lead, someone who knows how championship organizations conduct their business, and how championship players look and act and play.

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Most important, the Sixers need someone who is widely acknowledged to possess all of these traits. They need the capital he brings. The more you think about things in those terms, this is a move the Sixers have little choice but to make.

Even if Rivers does not prove to be a home run, he is unlikely to be a strikeout. However he leaves Philadelphia, the Sixers will have accomplished something. If they are the same dysfunctional mess, they will know that the problem lies within themselves.

If one of the most respected coaches in the game can’t teach Joel Embiid to do the things he needs to do to both dominate in the low post and make his teammates better within the framework of a conventional NBA offense, it will be fair to conclude that Embiid is what he is.

If he can’t build Ben Simmons into a legitimate primary scoring option, it will be fair to conclude that no coach can. If Rivers can’t mold those two players into the sort of tandem that dominates games, it will be fair to conclude that they simply cannot be molded.

In an ideal world, the people in charge of hiring the new head coach would have a demonstrated ability to decide these things for themselves. If that were the case, it would be easier to question their decision to make such a safe and obvious and conventional hire for what currently stands as an unconventional job.

It would be easier to raise an eyebrow at their sudden and drastic philosophical pivot from the future that would have unfolded under D’Antoni. The Sixers' courtship of the former Rockets coach made sense only if the front office had a reasonable level of doubt in Embiid’s ability to anchor a conventional championship team.

» READ MORE: 25 things to know about new Sixers coach Doc Rivers

If they had already arrived at a point where they thought D’Antoni was the best man for the job, Rivers departure from the Clippers shouldn’t have changed much of anything. These are two radically different coaches whose hirings would mean radically different things.

Yet, given who the Sixers are, the change makes perfect sense. The moment Rivers sits down at his desk, the building’s institutional knowledge will grow by some multiple of 10.

During his nine seasons in Boston, he and Danny Ainge built the Celtics into a championship team. For two seasons in Los Angeles, he served as the Clippers' president, and had final say in basketball matters. With the hiring of Lawrence Frank, he returned to coaching full time and spent three seasons in the employ of one of the NBA’s most forward-thinking executives.

As of Thursday evening, there was no indication that the official scope of Rivers’ duties would reach beyond the bench. That is a good thing. The Sixers' biggest need is a fresh, innovative, singular executive who understands where the NBA will be in five years and who can build a team that defeats it. As accomplished and respected and tactical as Rivers may be, he is still a product of the old NBA.

Again, though, these are the Sixers. Over the last five years, they have given us no reason to believe that they can or would make such a hire. With Rivers, they will at least get a guy who is a well-established winner. They will get an adult in the room. They will get a guy who has more political capital than Embiid or Simmons, who has more front office experience than Elton Brand, and who has seen more NBA basketball from more different angles than virtually anybody in the organization.

They will get a guy who will give them the ability to construct an important counterfactual: If this guy can’t make it work, maybe it really isn’t workable.