New York Times architecture critic Nicolai Ourossoff wrote that "Ratner quickly hired Shop Architects, a young New York firm, to spiff up the arena." (SHoP exterior at right.)
A lot of people have casually referred to the arena as a collaborative effort. But the the Barclays Center Arena Preliminary Official Statement (prepared by Goldman Sachs) makes it clear that Ellerbe Becket is the arena architect, while SHoP is merely working on the façade.
In other words, the basic orientation and design of the arena was not changed; the main change concerned the skin. (Original Ellerbe Becket design below.)
From the document
The Architect and the Façade Architect
The Architect, AECOM Ellerbe Becket Architects and Engineers, P.C., is a subsidiary of Ellerbe Becket, Inc., an architecture firm whose experience dates back to 1909 and which has designed over ninety (90) arena and stadium projects in the last twenty (20) years, including six (6) recent arenas for NBA teams: Conseco Fieldhouse in Indianapolis, Indiana, FedEx Forum in Memphis, Tennessee (winner of an AIA design award in 2006), AT&T Center in San Antonio, Texas, Quicken Loans Arena in Cleveland, Ohio, and TD Garden in Boston, Massachusetts. The Architect has also designed sports facilities internationally, including Guangdong Olympic Stadium in China and Saitama Super Arena in Japan. In addition, the Architect, which will contract with the Arena Design/Build Contractor to furnish the design services required for the Arena, has previously collaborated with the Arena Design/Build Contractor on prominent projects such as Conseco Fieldhouse, Time Warner Cable Arena in Charlotte, North Carolina, U.S. Airways Arena in Phoenix, Arizona, AT&T Center, Bank Atlantic Center in Sunrise, Florida, St. Pete Times Forum in Tampa, Florida, the i wireless Center in Moline, Illinois, and the HSBC Center in Buffalo, New York.
The façade of the Arena is being designed by ShoP Architects, P.C., the Façade Architect. The façade consists of an exterior wall system composed of glass and metal panels with horizontal steel bands encircling the building, as further described herein. See “THE ARENA PROJECT—The Arena.” The Façade Architect is a sixty (60) person practice founded by its five (5) principals in 1996 and has been a leader in the transformation of intricate theoretical design into easily understood construction models by rethinking architectural practice. Its current work includes a two- (2-) mile waterfront park along New York’s East River, and projects for the Fashion Institute of Technology and Goldman, Sachs & Co., both in Manhattan, and Google in Mountain View, California. Recently completed projects include Garden Street Lofts in Hoboken, New Jersey, Hangil Book House in Seoul, South Korea, The Porter House in New York City, and SanLiTun in Beijing, China. The Façade Architect’s work has won numerous awards, including the 2009 National Design Award for Architecture Design, awarded by Smithsonian’s Cooper-Hewitt, National Design Museum. The Façade Architect’s work has also been published and exhibited internationally, and is in the permanent collection of the Museum of Modern Art.