A rendering of the interior bowl of the proposed soccer stadium at PortMiami. (Source: Arquitectonica, 360 Architecture and Visual House)

MIAMI (CBSMiami) — While soccer superstar David Beckham eyes PortMiami for a possible Major League Soccer stadium, a group of Miami-Dade mayors have signed on against the plan.

During a debate Wednesday, opponents told the aptly named Downtown Bay Club, they don’t want a soccer stadium on the bay at PortMiami.

The David Beckham group insists an open air soccer stadium would be a jewel on now empty land, overlooking the water and the city skyline.

Leading an opposition, Royal Caribbean cruise lines, whose headquarters adjoins the proposed sight.

The two sides first debated on CBS4’S Facing South Florida.

“There is no alliance.There is one firm. This is just the self interest of Royal Caribbean,” said John Alschuler of Miami Beckham United on April 21st.

In response, President of the Miami Seaport Alliance, John Fox, said “We’ll have a letter from twenty local mayors opposing it.”

The group who opposes a Major League Soccer stadium at PortMiami announced Wednesday, they have now produced a petition signed by 11 mayors who oppose a port stadium.

Among them are leaders of Miami Beach, Homestead, Pinecrest, South Miami, Coral Gables and Cutler Bay Mayor Ed MacDougall.

“I think it’s more about taxpayer’s property that needs to be put to a better use, left to cargo and jobs,” said MacDougall.

Beckham’s group said nonsense, the property couldn’t possibly be used for ships. The waterway is too shallow.

“It does not at all interfere with port operations, either cruise or cargo,” said Neisen Kasden of Miami Beckham United.

Beckham has won over the Downtown Development Authority – convinced a port stadium would be a magnet.

“It certainly will help to brand downtown, just as the American Airlines Arena does. It will drive all that fan traffic to our restaurants and retail downtown,” said Javier Betancourt of the Downtown Development Authority.

Beckham was called overrated by opponents Wednesday, who added: U.S. soccer isn’t world class.

“The idea that this stadium is going to be beamed all over the world and we’re going to benefit from that is pretty much hokum,” said Fox.

The battle over soccer on the bay is still in the early rounds.

The prize fight over the proposed stadium at the port will be fought before Miami-Dade County Commissioners and a date for that has not yet even been considered.