Brent Schrotenboer

USA TODAY Sports

SAN FRANCISCO — Before his death in October 2011, Oakland Raiders owner Al Davis had been trying to solve one of the most difficult sports riddles in California.

How do you build a new NFL stadium in such a fiscally challenged state?

Davis wanted a shiny new facility to replace his old one, which opened in 1966. But another money-saving possibility also attracted his interest. His chief executive, Amy Trask, was having discussions with the San Francisco 49ers about building and sharing a new stadium in the Bay Area.

“It certainly was not his first choice, but he did understand the economic efficiency of sharing a building,” Trask told USA TODAY Sports.

The idea pretty much died when Davis did, said Trask, now an analyst with CBS Sports. Yet now there’s even more reason to consider it again, experts and various stakeholders told USA TODAY Sports. .

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More than three weeks after the Raiders lost in a game of relocation roulette, rejected in a bid to move south to Carson, Calif., Super Bowl 50 will kick off Sunday as yet another reminder of what could have been — and still remains possible — for the future of the Raiders in the Bay Area.

The game will be played at Levi’s Stadium in Santa Clara, a $1.2 billion facility that was financially supported by the NFL on the condition that it be built as a home for two NFL teams. One of those teams was the neighboring San Francisco 49ers, the only NFL tenant so far in a stadium that opened in 2014. The second possible tenant is a team that might never move in, no matter how much sense it makes for the Raiders, the 49ers, the NFL, Raiders fans and even the city that owns the land underneath it.

“Levi’s Stadium was built to accommodate two home teams,” said Jamie Matthews, the mayor of Santa Clara and chairman of the public stadium authority that owns the stadium. “We already have the locker rooms built for two home teams. We set up the LED lighting so they could change the whole feel of the stadium with the flick of a switch. All the environmental work on it has been completed, and all the work permits. If we had a second team, they could move in tomorrow.”

But they won’t, and only one person gets to say why not: Mark Davis, who took over team ownership after his father died. Davis didn’t respond to an interview request about whether his feelings on the subject might change now that his bid to move to Los Angeles appears to be a longshot. He has steadfastly rejected the possibility of Levi’s Stadium and instead hoped to build a separate stadium in Oakland. After not making progress there, he joined forces with the San Diego Chargers to pursue a $1.7 billion shared stadium in Carson, a suburb of Los Angeles.

That didn’t work, either. NFL owners rejected the Carson project on Jan. 12, sending the Raiders back to Oakland with no viable long-term plan except maybe one. Davis can see it again Sunday when the Carolina Panthers play the Denver Broncos in the Super Bowl, about 30 miles down the bay from the old Oakland Coliseum.

“There are things that could be changed to make it work,” said Marc Ganis, a sports consultant who helped the Raiders and Rams leave Los Angeles for Oakland and St. Louis in 1995. “The point is really an interesting one. Why have they not tried harder?”

The simple answer — they haven't had to. At least not yet.

Splitting costs in Santa Clara

There are plenty of superficial reasons for the Raiders to hate the idea of moving into Levi’s Stadium.

One is the red stadium seats, which clash with the Raiders’ silver and black but is consistent with the colors of the 49ers and Levi’s, the stadium’s naming rights sponsor.

Another is pride. A second team would be a subtenant of the 49ers, according to contract terms between the 49ers and the Santa Clara Stadium Authority, which owns the stadium and is governed by members of Santa Clara’s city council.

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But none of that should stand in the way of an attractive business deal for both teams, said Matthews, the mayor, whose city stands to reap more tax revenues with the addition of a second team.

The seat colors could be negotiable. And the 49ers would have a big incentive to create favorable terms for a second team. If stadium costs are shared, that could mean more money to keep for both teams.

“There’s a huge upside for (the 49ers) to want to attract a second team,” Matthews told USA TODAY Sports.

For example, the 49ers pay $24.5 million in rent for the stadium, an amount that only would increase by $1 million with a second team, said Gary Ameling, the city’s finance director. In theory, the 49ers could get the Raiders to split that rent to around $13 million for each.

The 49ers’ profits are private and not disclosed, but city records indicate the team collected around $83.7 million in NFL ticket revenue in 2014, with a 10% surcharge of $8.3 million going to the stadium authority to help pay for stadium costs.

A second team could get its own revenue boost from the stadium while doubling the number of NFL games at the stadium from 10 to 20 games per year.

Similar models have been attractive for other teams. After suffering as tenants at Giants Stadium for 25 years, the New York Jets are co-owners with Giants co-owners at MetLife Stadium, a $1.6 billion facility that opened in 2010. Likewise, after being rejected in their attempt to move to Carson with the Raiders, the San Diego Chargers have agreed on a deal to share a new $2 billion stadium in L.A. with the newly relocated Los Angeles Rams.

The Chargers will play the 2016 season in San Diego but could move to L.A. after that unless San Diego voters unexpectedly approve a new stadium to replace the team’s current 49-year-old facility.

Running low on options

That leaves the Raiders in limbo:

► They can continue on yearly leases in Oakland, playing in perhaps the worst stadium in league.

► They can hold onto the dim hope that the Chargers reject their L.A. option in the next two years. If they do, the Raiders would obtain the right to join the Rams there instead, according to a league agreement.

► They can even try to find a home in another city, potentially costing hundreds of millions for a relocation fee and in new stadium construction, subject to approval that some league owners might not be willing to give.

► Or they can accept a warm welcome and likely favorable financial terms at Levi’s, also subject to NFL approval.

The NFL deferred questions from USA TODAY Sports to the Raiders but confirmed that approval for the stadium’s $200 million in funding from the NFL was conditioned on a second team being able to play there. To make it easier on the Raiders at Levi’s Stadium, Ganis said the league might provide similar support. That could help pay for their share of Levi’s Stadium obligations, including a likely initial payment of $42 million that would be passed on to the city of Santa Clara.

The 49ers have a 40-year lease at Levi’s. They declined comment.

“We are completely focused on helping the NFL host a tremendous Super Bowl experience at Levi’s Stadium, and we understand the Oakland Raiders are focused on their own stadium project,” team spokesman Bob Lange said.

'Show me the numbers’

Mark Davis’ father didn’t like the idea, either, though it’s arguable that he hated it less than his son.

“Al was not as adamantly against it as is current ownership,” Trask said. “My conversations with Al went something like this: I would update him on my discussions with the 49ers, and he would immediately say, 'Hey, I’m not sharing that stadium.' And then after a beat or two, he would say, 'Show me the numbers.' "

The bottom line on the expense side of the ledger wasn’t too hard to figure out.

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“There’s an economic and environmental efficiency in sharing a building,” Trask said.

After Davis died, Trask said the subject waned and both teams went their separate ways, with the 49ers eventually helping pull off a California miracle of sorts. Levi’s Stadium is the first new big-league football stadium built in California in nearly 50 years. The facility is largely funded by the proceeds of personal seat licenses, naming rights and rent, plus an estimated $114 million in public funds. Matthews said the stadium’s remaining debt is only about $561 million, nearly half of the stadium’s cost less than two years after it opened.

Before Levi’s, the state’s NFL teams played in stadiums built in 1960, 1966 and 1967. Sunday’s game will be the first Super Bowl in California since 2003.

“It’s tough to build in California,” Trask said. “At the time the 49ers did what they did, it was a magnificent accomplishment because nobody else had been able to do it. From a league perspective, it was like, `Aha! One building solves two problems.’ Again, it’s just market efficiency: one building to solve the problems of two teams.”

The new stadium planned in Inglewood for the Rams will add more luxury to the state’s NFL neighborhood, but that project was possible largely because of the wealth of the L.A. market and the deep pockets of Rams owner Stan Kroenke, who planned to invest more than $800 million in the project.

Other owners in smaller markets would be challenged to build new stadiums without public funding, which can be tough to get these days.

'Far preferable to losing the team’

Even Raiders fans say Levi’s Stadium beats the alternatives outside of Oakland. The team recently opened a swanky new practice facility in nearby Alameda that cost around $8 million. They could keep using that, keep their Oakland name and just play games at the south end of the same Bay on Sundays.

“Would I like going to Levi’s stadium?” asked Jim Zelinski, a lifelong Oakland Raiders fan. “No, but it would be far preferable to losing the team to Southern California or another state.”

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Fans’ feelings don’t really matter in this equation, however. Neither do the opinions of the NFL, the city of Santa Clara or the 49ers.

Even though all might have good reasons to want the Raiders to move into Levi’s Stadium, none can make Mark Davis move his team against his will.

“I think the Raiders really want to do their own thing,” Ganis said. “They want their own stadium in the East Bay, but as a free agent they have a lot of places they can go.”

At least until they can’t.

Relocation is subject to league politics and approval from 24 of the league’s 32 owners. Davis has flirted with San Antonio, but the owners of the Dallas Cowboys and Houston Texans might try to block a move into their backyards. The team’s recent interest in Las Vegas also appears to be a longshot based on the league’s historical stance against sports gambling.

If the Chargers leave San Diego, Davis might look there, too. But he’d be trading a 50-year-old stadium in Oakland for a 49-year-old stadium in San Diego unless that city somehow suddenly can provide a suitable stadium for the Raiders after more than a decade of not being able to do so for the Chargers.

Finding the funds to pay for new stadiums can be even more difficult. Unless that new stadium is already built.

“Our fan base is huge here for the Raiders, and it’s huge for the 49ers,” Matthews said. “It’s certainly sufficient to carry both teams, but there are a lot of moving parts. … We’re going to wait until it shakes out. When and if they’re ready, we’re here.”

Follow sports reporter Brent Schrotenboer on Twitter @Schrotenboer. E-mail: bschrotenb@usatoday.com