NEW HAVEN, Conn. — The nonprofit foundation that runs the Connecticut Tennis Center has begun marketing the 13,500-seat stadium as an ideal site for conventions and business meetings, hoping to get more out of the building than a once-a-year tournament.

The state this summer added a new media center, completing $2.5 million in renovations that began last year with new facilities for players — including a lounge, a gym and a dining center.

The state approved spending for the improvements after buying the rights to the Connecticut Open tournament, the final women’s event before the U.S. Open, for $618,000 in 2013 to prevent it from moving to North Carolina.

Just over 50,000 fans attended last week’s event, well below the 76,480 who came in 2010, the last year it was a combined men’s and women’s event.

Anne Worcester, tournament’s director, said the attendance ranks among the highest for a WTA tournament and pumps about $10 million into the local economy. But, she acknowledges that other events are needed to keep the stadium viable.

The new facilities are ideal for corporate outings, trade shows, even weddings, she said.

“We have to be more than tennis,” Worcester said. “It’s absolutely essential.”

An organization can rent a meeting room or the dining room for $90 an hour, with discounts for nonprofits. The stadium court can be rented for six hours at a cost of $1,200. There are additional costs for the facilities manager and custodial staff.

“We would like to rent it out every day from September through July if we could,” said Lucas Bohr, the operations manager for the Tennis Foundation of Connecticut.

A local business group became the first to use the space, hosting about 150 people there for an event earlier this month. New HYTEs, the New Haven youth tennis and education initiative, is now housed in the new media center when the press isn’t using it.

Worcester said Yale University also is exploring holding meetings at the stadium.

There also was an attempt to stage an Aretha Franklin concert in September. That fell through, Worcester said, because it was not possible to get all the details worked out in time. The stadium last hosted a concert in 1994. Officials say holding live music there is logistically difficult because the stadium’s tunnels are too narrow to accommodate production trucks.

Mark Ojakian helped save the tournament when he was Democrat Gov. Dannel P. Malloy’s chief of staff and now sits on the tennis foundation’s board. He said the possibility of such events helped get support for the state’s investment in what he acknowledges was viewed at the time as a “big white elephant.”

“It wasn’t just like, the state’s going to give you money, we’re going to renovate this and make it nice for the players,” said Ojakian, who is now president of the Connecticut State Colleges and University system. “There was an expectation that the new board would be very engaged in making this facility have other revenue sources.”

Worcester said she’s optimistic the effort will be successful, especially if marketed properly.

“The corporations that we’ve engaged with love to be able to say, ‘Oh, our meeting is going to be in the players’ center at the Connecticut Open,” she said.