Oak View Group announced Tuesday it has switched its general contractor for the Seattle Center Arena project slated for completion in 2021.

Kirkland-based M.A. Mortenson Co., which provided OVG with pre-construction work for the arena rebuild, will replace Skanska-Hunt, the joint venture of Skanska and AECOM Hunt ducking out in response to market challenges and construction timing, according to a Dec. 11 news release.

The Seattle Times first reported on Dec. 8 that OVG was mulling a switch in general contractors after extending the arena rebuild timeline to 2021, and that Mortenson was the likely candidate.

“Mortenson’s local Seattle office spent five months leading pre-construction efforts on the arena project and is very familiar with our approach and goals,” said OVG senior construction executive Ken Johnsen in the news release. “Skanska-Hunt helped launch us, but I felt this project needed a dedicated single source team and we have mutually agreed upon a change. Mortenson is the nation’s pre-eminent arena builder and they are poised to complete this project in time for the Seattle Storm’s 2021 season.”

OVG had initially hoped to have the new arena — naming rights to be determined — finished by fall 2020, but pushed the timeline to spring 2021 in order for Seattle Hockey Partners to secure an NHL franchise (team name also TBD).

“Given the market challenges and shift in timing, it did not make sense for our joint venture to move forward to the next phase of the project, so we recently came to a mutually agreed upon decision to end our joint venture’s involvement with the arena project,” said Skanska executive vice president and general manager Kevin McCain in the Dec. 11 news release. “We are excited about the NHL coming to Seattle and we will provide full support to Oak View Group during this transition.”

The arena rebuild started as a $650 million project, but grew to $850 million, which Tim Leiweke said during the Dec. 5 groundbreaking was due to a commitment to keep the original roof and honor the 1962 Century 21 World’s Fair, for which the arena — then the Washington State Pavilion — was originally designed.

Mortenson’s sports arena work includes the U.S. Bank Stadium in Minneapolis, the upcoming Las Vegas Stadium that will be home to the NFL Raiders, a south end zone facility at University of Missouri’s Memorial Stadium and the Chase Center in San Francisco.

“We’re already deep into the transition process and look forward to assisting Oak View Group with its building of a world-class, landmark venue for our great city,” said John Nowoj, Mortenson’s senior vice president, in the news release. “Our company holds core to our mission: a commitment to excellence in economic inclusion and supplier diversity that will ensure we maximize the local impact and value of this tremendous project.”

OVG also announced on Tuesday it has brought on the Rockwell Group to design suite and club levels for the new arena, which will be 350,000 square feet larger than KeyArena.