It took just two years in the mid-'60s for the Spectrum to go from a gleam in the eye of sports mogul Jerry Wolman to America's showplace. Creating its replacement, a retail and entertainment hub that would be called Philly Live!, is taking considerably longer.

When developers released the first images of the project in January 2008, they showed a sprawling, neon-adorned entertainment mall that zigzagged its way across the stadium complex's vast asphalt domains, connecting Citizens Bank Park to the Wachovia Center with a diagonal indoor street. It wasn't exactly an urban, street-wall building, but its form was several notches better than the standard suburban shopping center and an improvement over that monoculture of parking.

Now, it appears that Philadelphia's memory-filled Spectrum - the original home of the Flyers and site of the Sixers' 1983 championship - is likely to be replaced by something far less ambitious. A new version of the project making the rounds at the Planning Commission offices shows a building about the size of a typical strip mall.

According to Spectrum owner Ed Snider, the one-story structure will house "the world's biggest sports bar."

And just how large would that be, Mr. Snider? "I don't know. Big. We're just guessing right now," said Snider, chairman of Comcast Spectacor, one of two private developers behind Philly Live!

You can attribute Snider's diminished ambitions for the Spectrum's replacement partly to the country's credit squeeze. Snider, whose company owns the Flyers, and his partners at the Baltimore-based Cordish Co. have had trouble securing financing for the original 350,000-square-foot, $100 million sports-themed extravaganza. They've been unable to sign a single tenant in the 30 months since they announced the Spectrum's demolition. So, they switched course.

Snider, who is also involved with the troubled Foxwoods casino, said the partners intended to start by building a smaller, test version with their own money. The scaled-down Philly Live! will contain about 50,000 square feet of leasable space, enough for the main sports bar and four smaller bars and restaurants. Snider said he and his partners planned to operate the food venues themselves. He declined to put a price tag on the venture.

If it works, the developers could add more buildings and tenants over time. Philly Live! would grow incrementally, just like a real city. That's not a bad strategy, retail experts agree, especially in these uncertain times.

The problem is that Philadelphia has no master plan for the sports complex, and that means there are none of the design standards that emerge from such a public exercise. There is no way to predict whether Philly Live! will grow up to be a real urban place with streets and a variety of uses. Without those city standards, the development runs the risk of turning into a jumble of inward-looking boxes.

Snider told me he expected to demolish the Spectrum within the next few months. Yet, city Planning Director Alan Greenberger said he still hadn't seen an actual design for the miniaturized Philly Live!

He doesn't know what materials the developers plan to use on the exterior. He doesn't know whether there will be windows to break up the outside walls. The developers have made it clear to him, however, that they intend to adorn the structure with plenty of signage.

This "bite-size" version of Philly Live! is so modest that Snider doesn't actually have to demolish the Spectrum to fit the project onto the sports complex parking lot (although the arena's days do appear numbered).

The current thinking calls for a square-shaped building immediately east of the Spectrum, located at the corner of 11th Street and Pattison Avenue, with street walls facing those two thoroughfares. Apparently, the internal diagonal street remains. There may also be outdoor terraces for cafe tables. Expect plenty of big-screen TVs.

The stadium complex wasn't exactly planned either, and its arrangement of isolated arenas exists by default. Unlike other cities, Philadelphia didn't have the courage to locate its new ballpark in the thick of the city. It's been too easy to pave over the South Philadelphia marshes.

Yet both the city, which owns the stadium complex land, and the venue operators have long dreamed of tying the sports oases together with nonsports activities.

Some of the advantages are purely financial. Why let all those sports fans disperse after the game when they might be lured into hanging around, and spending their money, on more entertainment in Philadelphia? If you add in concerts and other events, the area is busy 300 nights a year.

The Cordish Co. has made a specialty of building such postgame attractions in cities including Baltimore, Los Angeles, and Kansas City. Philly Live! might even become a destination for people without game tickets, Greenberger believes. Had Philly Live! existed this week when the Flyers clinched a place in the Stanley Cup Finals, it would certainly have been packed with people who wanted to be part of the vibe.

But the development's potential extends beyond the cash register. While the city never succeeded in building a sports arena downtown, Philly Live! offers a way to bring downtown, or something like it, to the stadium complex.

Greenberger said he looks enviously at San Francisco's Mission Bay development, a dense and vibrant urban neighborhood that grew up around Giants Stadium. It's a worthy model - though, sadly, one that may be out of Philadelphia's league, even though South Philadelphia continues to produce housing in the adjacent neighborhood. Still,a lifestyle center, like City Place in West Palm Beach, Fla., which mixes housing, retail, and entertainment in an urban-looking, but highly controlled, form, may be more realistic for the disconnected stadium complex.

Faux urbanism is better than no urbanism. But without a master plan to guide the embryonic Philly Live!, the only certainty is that Philadelphia's stadium complex will continue to grow by default.

Contact architecture critic Inga Saffron at 215-854-2213 or isaffron@phillynews.com.