Sports Authority has yet to announce an official closing date for its Denver flagship store, but the Sportscastle’s owner isn’t waiting to plan for the iconic building’s future.

Gart Properties president Mark Sidell said Monday the company is “continuing to look at ideas and options” for repurposing the faux Gothic building at 1000 Broadway as part of a larger redevelopment that could begin after the beleaguered sporting goods retailer packs up.

“The project will, in all likelihood, be a mixed-use project that would include some form of residential, some form of retail, restaurant, office of some amount and potentially a hotel use,” Sidell said.

“We think the Sportscastle building is a special building,” he said. “All of our current thinking incorporates that building as a cornerstone of the project.”

In addition to the Sportscastle, Gart owns most of the rest of the block along Broadway, including the covered parking garage next door and the office building spanning 1050-1060 Broadway, according to county records.

Behind the Sportscastle, at East 10th Avenue and Lincoln Street, Gart also holds a half-acre property that is currently home to a low-slung office building. On the other side of 10th, Gart controls the small Sports Authority customer parking lot, as well.

The Gart family has owned the Sportscastle since long before its Gart Sports stores merged with Sports Authority in 2003.

Holding court at the corner of 10th and Broadway, the ornate 1926 building was originally an automobile dealership.

In 1971, Gart Bros. Sporting Goods took over the building, transforming the space into a “Sportsman’s Castle” with 100,000 square feet of sporting goods retail space with a rooftop tennis court.

Annie Levinsky, executive director of Historic Denver, said her group has already had a “good initial conversation” with Gart about the potential of pursuing historic designation for the Sportscastle.

“We’re very hopeful it will be an opportunity to support another great adaptive-reuse project for an important building,” Levinsky said.

Sidell confirmed that historic designation is among the ideas being evaluated.

The odds that one of Sports Authority’s competitors would take over the Sportscastle lease through the bankruptcy auction that began Monday, however, are slim, Sidell said, given the fact that the lease is near its end.

The 75,667-square-foot Sportscastle lease ends Dec. 31, 2017, according to bankruptcy auction documents. Many other Sports Authority leases up for grabs nationwide extend into 2020 and beyond.

“We were in conversations before this all got started about getting (the Sportscastle) back,” Sidell said. “Even though they might love the location, the period of control you’d get by taking over that lease is not long enough to get someone excited about it.”

Emilie Rusch: 303-954-2457, erusch@denverpost.com or @emilierusch