What do you do when you can’t deal with L.A. developer Rob Maguire head-on?

You go around him.

That’s essentially what two Wall Street giants and a well-connected Beverly Hills financier did last week.

Specifically, they bought the mortgage debt on Maguire’s most ambitious development to date Playa Vista.

With that mortgage firmly in hand, and Maguire still $195 million in default, they are threatening to foreclose.

Just a few weeks ago, those same three entities were negotiating with Maguire and his mortgage bankers to become Maguire’s equity partners in Playa Vista, where DreamWorks SKG plans to build its studio campus. Those talks ended with no deal being reached.

So last week, they bought the Playa Vista mortgage instead, effectively gaining control of the project through debt, rather than equity.

Buyers of the mortgage debt are two real estate investment funds that are managed by affiliates of Morgan Stanley & Co. and Goldman Sachs & Co., respectively.

Those two funds confirmed last week that they have acquired an 83 percent stake in the $150 million (original principal) Playa Vista mortgage.

That loan has been in the process of being foreclosed upon since early March, when the Chase Manhattan Bank-led original lender group initiated its foreclosure action.

The buyer of the remaining 17 percent stake in the Playa Vista mortgage is another real estate “opportunity” fund, which sources close to the deal refused to name and public records did not identify.

The entity that orchestrated the deal is Beverly Hills-based Pacific Capital Group, headed by financier Gary Winnick.

The deal calls for Pacific Capital and its trade union pension fund clients to eventually take a major stake in the development as well, sources said.

They said that Winnick frustrated by his efforts to close a Playa Vista equity investment deal with Maguire took the initiative in bringing his team together with the Goldman and Morgan funds.

If successful in taking over the controversial 1,087-acre mixed-use development, the newly formed Goldman-Morgan-Winnick team plans to commence construction on Playa Vista’s first phase “as soon as possible,” according to a well-placed source.

Playa Vista’s first phase is expected to include the DreamWorks campus the first major entertainment studio to be built in the L.A. area in more than a half-century.

Last week’s developments are the latest chapter in a tumultuous battle to take control of the multibillion-dollar Playa Vista project near Marina del Rey. The battle has frustrated DreamWorks’ principals to the point where consideration had been given to dropping out of the development altogether.

But the deal confirmed last week brings new hope that the project may finally break ground unless Maguire decides to seek bankruptcy protection or pursue some other legal option.

Sources said that the new mortgage-holders and Winnick intend to offer Maguire a role in Playa Vista’s ongoing development, but a significantly diminished one.

If Maguire refuses to accept a lesser role, the mortgage-holders plan to proceed with the foreclosure action that the original lender group initiated in early March. If that happened, the mortgage-holders could take title to the property as early as July.

Citing “confidentiality agreements,” Maguire declined to comment on the sale of the mortgage other than to say his firm has “long and favorable relationships” with both Goldman Sachs and Morgan Stanley, and that the Playa Vista property’s prospects “get more attractive every day” as the Westside real estate market continues to recover from the recession.

Asked about the foreclosure threat, Maguire said he “absolutely” expects to remain intimately involved in Playa Vista’s development.

Some sources familiar with the negotiations said they doubt Maguire would respond to eventual foreclosure by seeking bankruptcy protection. But they conceded such a move remains a possibility, and one that could potentially threaten DreamWorks’ participation in Playa Vista.

One source also said he’s aware that at least some of the other parties to the Maguire-led partnership that now owns the property are frustrated with Maguire’s tactics and are trying to reduce his authority to act on the partnership’s behalf.

Executives of Maguire’s principal partner in the current Playa Vista partnership Howard Hughes Corp., which has had an interest in the property since its namesake aviator purchased it in the 1940s weren’t available for comment last week.

A partnership including Maguire’s development company Maguire Thomas Partners, Howard Hughes Corp. and others had secured $150 million in loans from a Chase Manhattan-led lender group when Maguire’s group bought into Playa Vista at the height of the local economic cycle in the late 1980s.

The project sat idle for years, amid the subsequent recession. But in late 1995 came word that DreamWorks would build its futuristic campus at Playa Vista.

Then last February, Maguire tentatively agreed to a $200 million Playa Vista recapitalization deal offered by Winnick. A key player on Winnick’s team is Washington, D.C.-based Union Labor Life Insurance Co., which invests union pension money.

The banking group had reportedly agreed to accept about 65 cents on the dollar as payment for the mortgage debt on the property.

(Sources subsequently confirmed that an affiliate of Century City-based real estate investment group Colony Capital Inc. had agreed to become a participant in the Playa Vista development. But Colony is not expected to become part of the Playa Vista team, sources said last week.)

Executives of the Morgan and Goldman real estate funds offered only a brief statement last week confirming their collective stake in the Playa Vista mortgage. Winnick declined to comment on the purchase of the mortgage, nor were DreamWorks official available for comment.