During a long weekend last August, thousands of energized fans, many dressed in elaborate costumes, packed the Air Canada Centre in Toronto for three days of frenzied competition. It’s not uncommon for this venue, which seats just under 20,000, to sell out. But the crowd didn’t come for hockey, basketball, or even a concert. There were there to watch pros play video games.

Fans clamored for seats to see teams playing in the North American championship series for the League of Legends, one of a number of popular multiplayer online battle arena video games. Players squared off at center court, their every move broadcast to the arena on massive screens. Though it was the highpoint of the season, it’s wasn’t an outlier in terms of crowd size. It’s one of many indications that this growing sport needs newer, bigger spaces to play.

Competitive video games, or eSports, are on the way to becoming a $1 billion industry by 2019, and have drawn huge crowds at other iconic venues across the United States, such as the Staples Center in Los Angeles and New York’s Madison Square Garden. The rapid growth of the live aspect of the industry has many arena owners, as well as architects, seeing an opportunity, as well as the emergence of a new kind of sport venue.

“There’s a number of large-scale live video game events occurring, and we just see that continuing to grow in the future,” says Brian Mirakian, Principal and Director at Populous Activate, the branded environments wing of the global architecture and design firm. His company has created iconic stadiums such as Baltimore’s Camden Yards, Emirates Stadium in London, and various World Cup and Olympic-level arenas. Mirakian sees opportunity in a new generation of venues designed with the fast-growing world of competitive video games in mind, a topic he’ll be discussing at a SXSW panel in Austin this March. As the fan experience for all sports become increasingly digital, designing a venue for video games may offer lessons for all types of stadium architecture.

“How can we design the next generation of these buildings?” he says. “In the same way Centre Court was designed for Wimbledon, let’s design the next purpose-built, competitive arena for eSports.”

The digital playing field expands

Games with huge followings, such as Dota 2, Counter-Strike, and League of Legends, have created a demand for well-equipped venues that can offer a captivating experience to fans, forcing stadiums to adapt to the digital age. With growth pegged at nearly 20 percent a year globally, eSports competitions attract a young, digitally-savvy audience around the world that draws sponsors, and most importantly for stadium owners, can help fill seats.

“It’s what every traditional league inspires to,” Mirakian says, “having fans who are young, global, and increasingly diverse.”

Owners of traditional venues in the U.S., such as NBA and NHL arenas, are increasingly seeing eSports as a route to extra revenue, and are adapting stadiums to the needs of bandwidth-heavy video game events. The Houston Rockets NBA team recently became the first in the league to hire a video game exec to manage eSports opportunities. Mirakian says he has lots of clients from the traditional sports industry looking for ways to program more eSports events

“Every traditional pro sports team is investing in eSports,” says Wim Stocks,GM/CEO of WorldGaming and Collegiate Star League, two video game sites. “It’s a way to bring millennials in. The median age of a Major League Baseball viewer is 53 years old. They’re doing it to engender a much younger and engaged audience.”

While eSports often get blithely dismissed as not being a “real sport,” numbers suggest these competitions are, as Stocks says, “the new mainstream.” Twitch, a streaming site that broadcasts video game play that was purchased by Amazon for $1.1 billion, now racks up more than 100 million unique viewers a month. Disney and BAMtech, the broadcast platform for Major League Baseball, just purchased the broadcast rights for League of Legends for $350 million, mostly due to the fervent audience.

These kind of numbers explain why Mirakian and Stocks are so bullish on the burgeoning live aspect of the industry, and future stadium expansion. Early examples have proven to be big successes. The recently opened MLG.tv Arena in Columbus, Ohio made $4 million in revenue during its first year, and UC Irvine is in the process expanding its eSports arena, the first such dedicated space on a college campus. Mirakian sees temporary venues for these events becoming common rather quickly, while purpose-built venues will come online in the next few years. He also foresees gaming companies, such as Riot Games and Blizzard Entertainment, making investment in their own arenas and venues.

“This is a fan culture that wants to have a deep dive experience”

How stadium design can level up

According to Mirakian, creating a custom eSports arena requires a technologically advanced design that offers a content-rich, thematic environment, something that connects fans to the action akin to an immersive concert experience. These spaces need to have a backbone of high-speed digital connections that can both record and broadcast within such a media-rich environment, and support an advanced media projection system.

“This is a fan culture that wants to have a deep dive experience,” he says.

He envisions seats that are responsive, which may include individualized consoles that allow fans to pull up data and custom content, perhaps even haptic feedback of wearable devices that literally allow the fan to feel the action. It’s a tech-rich, immersive environment that blurs the boundaries between the virtual world of games and the physical world the audience is in. With advancements in augmented and virtual reality, an even more theatrical element is possible, where characters in the game are displayed like holographs above the crowd.

“When you go to the venue that’s both personal and communal, it starts to feel like a rock show,” says Mirakian. “The fans are as excited as anything you’d see at a traditional sporting event. When critical moments happen in the game, you’d think someone just scored a goal in game seven of the Stanley Cup. It’s amazing.”

Before purists suggest that this plugged-in experience is anathema to the “real” sports experience, just look at trends in traditional stadium design. Today’s high-end, digitally friendly stadiums were built with the “challenge of the couch” in mind, to entertain a generation used to the instant gratification of mobile media and home entertainment. The new Sacramento Kings’s new Golden 1 Arena, arguably the most high-tech in sports, is designed to be a “communal fireplace” fueled by high-speed digital connections. Viewing competitions on multiple screens has become the new norm.

“We see this as an incredible opportunity emerging,” says Mirakian. “It’s a virtual competition, but it’s bringing people together, which is what people love. There’s an incredibly passionate online community, but there’s an amazing passion for fans to be together. It’s exciting imagining what this live experience can be.”