Mayor Muriel Bowser, right, and Ted Leonsis announce plans Wednesday to build a sports arena at St. Elizabeths in Southeast. (Bill O’Leary/The Washington Post)

A number of officials, including D.C. Mayor Muriel E. Bowser, repeated the phrase under the glaring sun on the east campus at St. Elizabeths on Wednesday afternoon.

The proposed $55 million complex scheduled to open in 2018 “is bigger than basketball,” they emphasized. The site, they hope, will become an entertainment hub and economic engine for a Southeast Washington community thirsting for investment.

But basketball will be the 118,000-square-foot center’s primary function as home for Ted Leonsis’s professional basketball teams. The site will feature a practice facility for the Washington Wizards and a 5,000-seat arena that will become the home floor for the WNBA’s Washington Mystics and, in the future, the Wizards’ D-League affiliate.

The development would complete Leonsis’s effort to secure a dedicated space for his basketball entities to compete with the rest of the industry, particularly in the case of the Wizards.

Nineteen NBA teams have built standalone practice facilities while the Wizards have remained at Verizon Center, where they practice on a cramped court and share workout areas with other teams based in the building.

Leonsis envisions the facility yielding the same impact on the Wizards that Kettler Capitals Iceplex, located in Arlington, has had on the Washington Capitals since it opened in 2006.

“It strengthens our position with players and staff in that they’re going to have the real estate, the space, the workout areas, the training areas, the classrooms. We just don’t have that at Verizon Center,” said Leonsis, whose company, Monumental Sports & Entertainment, also owns the Capitals.

“And I witnessed firsthand with the Capitals. Once we built Kettler Capitals Iceplex and we changed our [American Hockey League] affiliate in Hershey, that the bringing together of our AHL, practice facility and Verizon Center, and looking at them all as a platform, really elevated the team.”

Leonsis said he visited the Chicago Bulls’ practice facility, which opened last September, and will use other complexes as models while adding on to them.

The Wizards’ facility is expected to boast the typical amenities: practice courts, swimming pools, training rooms, a players’ lounge and a kitchen, among them.

But Leonsis also mentioned he wants digital studio capability and a room for virtual reality technology.

“You have to keep improving and keep up with the Joneses as they say,” Wizards General Manager Ernie Grunfeld said. “If you come to our facility, every year you see something change and something get a little bit better. . . . It’s almost a necessity nowadays to have your own practice facility.”

Beyond the everyday function, the Wizards hope the complex will serve as a recruiting tool to lure free agents and keep their own players in the District.

All-star point guard John Wall, one of two Wizards players in attendance Wednesday along with Bradley Beal, explained having to share resources at Verizon Center has created inconveniences since he joined the team as the No. 1 pick in 2010.

“We’ve realized that plenty of times,” said Wall, due to become a free agent in 2019. “Sometimes we want to work out at certain times and the girls, you got to get them their space because they got practice and stuff. We want to get on the court but we can’t. So I think it’s going to be great for them to have their own arena to play. And then you have the opportunity to work out at any time you want to without miscommunication and stuff like that. It’s stuff you have to deal with now but it’s exciting that we’re going to fix it in the future.”

While the Wizards will continue to play their home games in Chinatown, the Mystics are planning to shift their entire operation to the new facility once it is completed.

Leonsis emphasized relocating the Mystics from cavernous Verizon Center to a more intimate setting is practical. Though the Mystics are among the WNBA’s leaders in attendance and have finished first several seasons, Leonsis explained the numbers are misleading because sponsors often buy tickets and empty suites are counted toward attendance figures.

“Not only is it a perfect size, it’ll be an atmosphere that’s loud, that’s exciting, that’s collegiate, in a way,” said Leonsis, who added the Mystics will be the first WNBA team with their own practice facility and arena. “And it’ll help the players because you play sometimes at Verizon and there’s 20,000 seats and there’s 4,000 people in the building, it feels like you’re not successful.

“Now they’ll always feel successful. And once they sell out, that kind of gets the spiral going up.”

The arena, Leonsis said, will also serve as the home for the Wizards’ future D-League club. Last week, the Indiana Pacers bought the Fort Wayne Mad Ants, the Wizards’ D-League affiliate last season, leaving the Wizards as one of just 11 NBA franchises without a D-League affiliate for the upcoming campaign.

“We will now start serious discussions about can we get an expansion team,” Leonsis said. “We know where we can put it, and I think it would work great here. I think in a 5,000-seat arena that tickets can be priced correctly in the marketplace. It’s close enough to Verizon but can still be programmed and marketed separately.”