With developer Valve creating the operating system, SteamVR for the VR headset HTC Vive, which launches April 5, eSports could eventually evolve into a virtual reality experience. Valve is the developer behind two of the most popular eSports games in the world today: Counter-Strike: Global Offensive (CS:GO) and Dota 2.

Chet Faliszek, writer and virtual reality evangelist at Valve, sees a future for eSports through HTC Vive.

“While we have The International and events where people are watching people play games, it is fun to watch someone play a VR game because they’re physically moving around in this space and making these motions that people can understand what’s happening,” Faliszek says. “It lets a broader group of people watch. It’s great spectator sport.”

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Vive launches with over 50 games and there are hundreds of additional games in various stages of development. The Vive isn’t launching with any eSports games, but Faliszek believes developers will explore this area in the future.

“Look at last year’s content versus this year’s,” Faliszek says. “Developers are more comfortable with how Chaperone works versus just moving in the space.”

“VR eSports is first going to be about spectating,” Faliszek says. “VR changes the game so radically. You’d need to make a game built from the ground up, and we’ll see games made for eSports.”

According to research firm Newzoo, the number of eSports fans will grow from over 256 million this year to over 345 million by 2019. And as more people spend time in virtual reality games, they’ll become more used to playing and watching in an alternate reality.

“As people get more and more comfortable in this space they forget about where they are,” Faliszek says. “When you do the long sessions, you forget about doing what you’re doing.”

That’s good for the future eSports pros who will be spending long hours every day practicing. A typical pro gamer today will practice for eight to 12 hours a day.

“People get mad when they call the players athletes today, but that’s going to flip back around because some of these games become very physical (in VR),” Faliszek says. “The guys playing Dota are athletes, so it’s a silly argument. But it’s fun to watch the experience.”

Joost van Dreunen, CEO of SuperData Research, believes the potential for competitive gaming in virtual reality is large because the combination of the two leverages their best traits.

“ESports present a theater in which high level players take gameplay to new heights, constantly employing new tactics and adding a layer of drama to video game play,” van Dreunen says. “Virtual reality allows viewers to follow the spectacle more seamlessly.”

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It also makes sense from a business perspective, since van Dreunen says the consumer profile for eSports fans and VR enthusiasts has a large overlap: Both are tech-savvy, early adopters that spend well above average on having the best possible gaming experience.

“This also means that the addressable market is narrow, but in this early stage of VR’s lifecycle, it will be the hardcore PC gamers that will initially make up the bulk of consumer demand,” van Dreunen says.

In addition to the HTC Vive, developers have other VR systems to potentially build eSports games for. Facebook has begun shipping Oculus Rift to consumers and Sony will launch PlayStation VR this October for PlayStation 4 gamers.