Whenever Frances Tiafoe competes in D.C., he expects to see familiar faces throughout the stands. While playing for the Washington Kastles last week, Tiafoe delighted a crowd that included his parents, his twin brother, Franklin, and a number of friends he knows from the D.C. area.

That part is to be expected. What proved to be unusual was the setting. The Kastles have made the 700-capacity venue on the Union Market rooftop their home this summer. (Kastles owner Mark Ein also owns City Paper.)

“I mean, how many times are you going to play on a roof in your life? So that’s one off the bucket list for me,” Tiafoe said after the team’s home opener on July 15. “I was happy. I played some great tennis tonight. I hope the fans really enjoyed it. I saw a ton of my friends. That’s what it means to me to play here in D.C.”

The Kastles players—and even some of their opponents—have embraced the unique experience over the last week and a half after spending the past five years playing indoors at The George Washington University’s Charles E. Smith Center. The team started in 2008 at an outdoor arena on the site that would later become CityCenterDC, followed by another outdoor venue at the Southwest waterfront three years later.

But because of the rooftop’s comparatively low capacity (Smith Center held around 2,000 fans), there is no guarantee that the team will return to Union Market next season. Fewer ticket sales mean less revenue and hosting a professional tennis event on a roof comes with a hefty price tag.

“Our intention is to make it longer term, but like anything, in one year you learn a lot,” says Ein. “That’s probably the biggest part of the challenge is just the size. It’s also not cheap to build a stadium on the roof as it turns out.” Ein declines to give a specific financial figures. 

City Paper has reached out to Union Market for comment and will update this article if we receive additional information.

First-year Kastles player Kaitlyn Christian has played on courts all over the world and even starred in a 2017 Hollywood movie about tennis.

Christian, 27, hails from Southern California and served as Emma Stone‘s body double in the film Battle of the Sexes, about Billie Jean King‘s famous mixed-gender match against Bobby Riggs in 1973. The filming took about three weeks on tennis courts around Los Angeles. Christian says she competed on rooftop courts at a club in L.A. during her junior career, but this is the first time she’s played on a roof as a pro.

“It’s really cool,” Christian says. “It’s a really unique court. It’s nice that it’s very intimate. You can’t fit too many people in it, but you can hear them on the court. It’s really special and I’m really enjoying playing on it.”

But being outdoors also means players are at the mercy of the weather. Last Wednesday, July 17, the Kastles postponed their match against the Orange County Breakers before canceling it for the evening due to rain. The match will be made up with a double-header when the Kastles play the Breakers on July 31 in California.

On Monday of this week, the Kastles began their match against the Orlando Storm as dark clouds loomed above. Midway through the men’s double match, the downpour began, sending the near capacity crowd sheltering in the small stairways inside Union Market.

The team quickly made the decision to play the remainder of the match at the indoor tennis bubble at the East Potomac Tennis Center, a 15-minute drive away. Within a half hour, the players went from playing in front of a packed crowd on top of a roof to competing on an indoor court with a few dozen onlookers.

“It’s sometimes tough,” says Kastles player Yoshihito Nishioka, who had his doubles match with Bruno Soares interrupted. “We cannot do like much warming up before the match started. We have to focus like very short … If opponent playing good, the match is over. It’s very tough to play in these situations, but it’s good to play because we have to focus first point til end. It’s pretty similar to normal tournament as well. It’s good training.”

The Kastles have two home matches remaining this season. Venus Williams is set to make an appearance this Thursday, July 25, while Nick Kyrgios is scheduled to be in town on Saturday, July 27. As of the now, the weather forecast looks clear.

“You don’t [always] get action that close, a unique location, team competition,” Soares says when asked if he wanted to play at the rooftop again next year. “I think it’s something good to be in such a unique location in this city. For us, it’s amazing, and I would love to come back and play there again.”