It often appears the Celtics try to operate behind a veil of secrecy. But if you want to get an idea of what they're attempting to do, look at their actions.

Their rookies are still unsigned and they still haven’t made a decision on Tyler Zeller. That keeps them in position to make a potential blockbuster trade.

Last summer, the Celtics held off on finalizing contracts and trades that had been agreed to in principle in order to maintain maximum flexibility. They waited until late July to sign their two first-round draft choices, to formally re-sign Jae Crowder, and to make the David Lee trade official. That all happened on July 27, because that's when the path to acquire a star had finally been exhausted.

They're waiting for that chance again this summer.

Teams have handed out money like candy this offseason and Zeller missed out on all the fun as a restricted free agent. That makes his situation particularly compelling from a big-picture perspective.

The Celtics can withdraw their qualifying offer of $3.7 million at any point through July 23, and they have the right to match any offer sheet Zeller might sign. The issue is there only seven teams with enough cap space to make him an attractive offer. Most of those teams have already acquired centers this summer, and others are already loaded at the position. The chances of any of them tossing money at Zeller seems improbable.

Teams over the cap could sign Zeller to an offer sheet using an exception, but the lone exception more lucrative than Boston’s qualifying offer of $3.7 million is the mid-level, which is worth $5.6 million.

You’d think Zeller, still just 26 and a proven rotational center, would have received an offer like that already. In fact, it’s quite possible that he has but hasn’t signed it. And if he hasn't, then he’s still waiting to sign his qualifying offer.

Why?

The conventional answer is that he’s hoping to negotiate a new contract with the Celtics. But the more probable reason is that Zeller is aware of a potential sign-and-trade scenario that’d pay him an exorbitantly large sum of money.

Remember Keith Bogans? When the Celtics traded Kevin Garnett and Paul Pierce to Brooklyn, the Nets needed a salary to make the deal valid. So they signed Bogans for $5 million and included him in the trade. It’s technically more complex than that, but, in a nutshell, Bogans’ bloated contract made the trade legal.

Of all the star players whose names have been discussed as options for the Celtics, there’s really only one in which a sign-and-trade for Zeller would actually be necessary. It’s the one no one takes seriously because it sounds so outrageous: The scenario where the Celtics acquire both Russell Westbrook and Blake Griffin.

That's what the Thunder are hoping to do next summer, according to The Vertical's Adrian Wojnarowski. But the Celtics, theoretically, are a team with the assets to do that now.

Let’s play it out. Let’s say the Celtics were to acquire Westbrook, and he extended his contract to keep him signed until the summer of 2018. At that point, the Celtics would have almost no cap space. So if they were to then trade for Griffin, it’d be necessary to use a sign-and-trade for Zeller to make it work.

The value of the contract would vary greatly depending on which players were given in return for Westbrook and Griffin. But no matter the amount, it’d be for a hell of a lot more than his qualifying offer of $3.7 million. Double. Triple. Maybe even quadruple. Based on the cards Zeller has been dealt, it’s a no-brainer for him to wait . . . even if there’s only a miniscule chance of a blockbuster trade.

Contrary to popular belief, the Clippers aren’t rebuilding if they do trade Griffin. They’d simply be shuffling the deck to find a better mix, and adding assets (like a Nets pick) in the process. So there's a reason Zeller and the Clippers could do business. Despite signing two veteran power forwards, Los Angeles still needs a true backup center; Doc Rivers absolutely isn’t playing either of his two rookies. Zeller’s salary would also be non-guaranteed after the first year, making him a valuable trade asset entering the 2017 offseason.

The names and faces involved in this wild hypothetical scenario also have a history of making successful high-stakes business transactions. Trust is integral to any relationship, especially one with implications so significant.

Rivers and Danny Ainge worked together for years in Boston. And Ainge and OKC general manager Sam Presti have worked together numerous times, too. Presti’s first move as GM sent Ray Allen to Boston, and years later they made the shocking Jeff Green-for-Kendrick Perkins swap.

Two of the key players involved, Zeller and Griffin, happen to be represented by Excel Sports Management agents Sam Goldfeder and Jeff Schwartz. They also represent Boston’s master recruiter, Isaiah Thomas, who’s been in California this past week. Clippers forward Paul Pierce is also represented by Schwartz. Remember when Kevin Love showed up with Schwartz at a Red Sox game and they happened to bump into Rajon Rondo?

There is history, both in regards to actions and relationships, to suggest that all the ingredients are there for this so-called pipedream of a trade scenario to materialize. Enough of a chance, certainly, that Zeller and his agent are actually willing to bide their time in the hopes of landing a situation in which the payoff and opportunity would potentially be greater.

And in the more likely event that there's no trade, Zeller could still sign his $3.7 million qualifying offer with the Celtics. Or an offer sheet with another team. But he doesn't have to do it now, and he may benefit by waiting.

Want to know what’s actually outrageous? Thinking the Celtics are just waiting to sign their rookies because they haven't gotten around to it. Thinking that a young, cheap player like Zeller will go unsigned. Thinking that the Celtics aren’t actually angling to make a franchise-altering move.

There’s no guarantee it happens. The chances are it probably won’t, considering the complexity of the situation. If they re-sign Tyler Zeller and/or sign the rookies, that’s when you'll know it’s over.

But for now, the Celtics are taking the necessary actions to assure they can have a whale of an offseason if the opportunity presents itself.