Construction at Barclays Center hit a major milestone Thursday with the announced "topping out" of structural steel by developer Forest City Ratner.

Members of Ironworkers Local 361 joined CEO Bruce Ratner at the site to celebrate completion of the installation of 10,400 tons of structural steel, which began in November 2010.

At the event, Ratner vowed to complete Barclays Center in eight months—just in time for the future home of the Nets basketball organization's scheduled Sept. 28 opening date. 

The milestone comes a week after word leaked out about the bankruptcy of an Indiana-based manufacturer of specially weathered steel panels for the stadium's exterior.

Today's announcement does not cover the installation of the exterior panels, which has not been completed.

While a FCRC representative said the bankruptcy of the steel panel maker would not affect its construction timeline, an Atlantic Yards Report blog post claimed the target completion date had been moved back a week to Aug. 30, with final landscape work and sidewalk installation finished by Sept. 25—just three days before a scheduled Jay-Z concert to commemorate the opening of Barclays Center.

Despite doubts that the stadium would be finished in time, Ratner held fast to the target September opening date at today's ceremony.

"In just eight months we will open Barclays Center and bring many exciting events here, where your hard work will be appreciated by millions of people for years to come," he said to the union workers at the site.