In a spare, harshly lit classroom at Seoul's Game Coach Academy, the mood is tense. Six teenagers are sitting side-by-side at their computers playing a game called Overwatch, as two coaches pace behind them and shout out advice.

"Don't get sloppy," they call out. "You need to be catching the other team's mistakes!"

The six young men are students at Game Coach Academy, a government-accredited gaming camp in Seoul, South Korea, that offers training programs for aspiring professional gamers. The game they are playing, Overwatch, is a sci-fi first-person shooter in which two teams of six battle to secure certain objectives, such as holding a point for a set amount of time or escorting a payload along a designated route. Each hero has a unique toolbox of abilities that they can deploy in battle, although the tricky part is knowing how and when to use them, effectively countering your opponents' team composition with your own.

Right now, the students are having difficulty penetrating the aggressive defense set up by the opposing team, six other students in the next classroom over. Their attempts to break through were thwarted twice already by the more agile enemy team's DPS heroes -- offensive players whose role is to assassinate high-value targets on the other side.

"They should be changing their composition," says one of the coaches, clearly frustrated. "They need to get into a quicker offensive tempo."

On-screen, an enemy hamster in a spherical robotic suit (aptly named Wrecking Ball) careens into their ranks. The students punch their keyboards furiously, vanquishing the intruding rodent, but it's not enough to swing the round in their favor.

"After they lost the first match, they just lost their nerve," says the assistant coach.

The students look crestfallen. Later, they will be given homework: watching tape of the match they just played in order to pinpoint what they did wrong and practicing a set number of hours on their own.

For the uninitiated, the idea of doing homework on a game where hamsters are running around in robotic suits might sound strange. But it becomes much less so when you consider that esports is a multimillion-dollar market with a vast following that has, in recent years, dramatically upped the stakes of what it means to game professionally. Market intelligence firm Newzoo estimates that esports revenue will top $900 million this year, growing to $1.5 billion by 2020, buoyed by big-name investors like the Miami Heat and Paris Saint-Germain Football Club.

In South Korea, widely credited as the birthplace of esports and famous for its PC bang (gaming café) culture, competitive gaming is something of an unofficial national pastime. As esports celebrates a breakthrough moment with its recent inclusion in the 2018 Asian Games, legions of young South Koreans -- like the students at Game Coach Academy -- aspire to be the next "Faker," the South Korean-born LeBron James of the pro gaming world who reportedly makes $2.5 million a year.

Game Coach Academy seeks to bring clarity and structure to a fledgling industry that doesn't yet have a well-defined career trajectory.

"If you want to be a soccer player or a pianist, there are clear answers as to what you should do -- either join a soccer training program, or take piano lessons," says academy director Lee Seung-hun. "But no such thing existed for professional gaming. We wanted to be the ones to provide the solution."

Coaches themselves are retired pros, and the academy has already graduated five more since opening in 2017, including "Fate," an Overwatch player signed to Los Angeles Valiant in Blizzard's Overwatch League. Their parent company, Bigpicture Interactive, owns a professional Overwatch team of its own: Element Mystic.

One of the academy's top Overwatch prospects is 16-year-old Choi Tae-min, a DPS player with preternaturally good aim who goes by the handle "MER1T."

"I chose that name because I want to be a player that only has strengths, no weaknesses," says Choi. "Right now, I think my strength is my good physical."

"Physical" is Korean gaming slang for in-game physical qualities like aim and character control.

He pauses, unable to think of a weakness. Coach Kim Hyo-han interjects with a stern look.

"His weakness would probably be that he shies away from situations that he isn't comfortable with."

Players at Game Coach Academy practice their Overwatch skills in Seoul, South Korea. Max Kim for ESPN

Under the tutelage of his coaches, Tae-min is working on his shot-calling, a fundamental skill in a game like Overwatch, where games are won or lost by split-second decision-making that requires snappy and efficient communication among teammates. That, he says, was the main takeaway from his first recent unsuccessful pro team tryout.

"I felt that the level of their shot-calling and communication was just on another level from us," he says. "Training here, I feel like I'm able to learn these aspects of the game in greater detail."

Every Saturday, Tae-min makes the three-and-a-half-hour bus trip from his home in Gwangju to the academy with his father, Choi Seong-nam, who, despite being a self-proclaimed technophobe, has taken a spirited interest in his son's pro gaming aspirations. When Tae-min first told his parents about his decision to become a professional gamer earlier this year, his father went on YouTube to do research.

"I watched videos about pro gaming, interviews with professional gamers and learned how competitive it was," he says. "I read about the difficulties and obstacles of this path, and I understood that in order to be a pro, you need to have a serious attitude."

He decided to enroll Tae-min at Game Coach Academy earlier this year, hoping the specialized instruction would do him good. "With everything, unless you're a natural genius, you need to go through certain steps," he says. "It's reliable to have coaches teaching him."

At home, Tae-min dedicates every other hour of his day to Overwatch. On school nights he plays for the five hours he has between getting back from school and going to bed. On Sundays he practices for up to 10 hours. He no longer meets friends to game casually at PC bangs.

"If you want to be a soccer player or a pianist, there are clear answers as to what you should do -- either join a soccer training program, or take piano lessons. But no such thing existed for professional gaming. We wanted to be the ones to provide the solution." Lee Seung-hun, academy director

"When he's playing, I close his door and lower the TV volume," says his father. "We also try to time dinner so that it disrupts his playing the least."

The sheer repetition sums up the ethos of competitive gaming in South Korea. "I think Korean players are just crazy about gaming to a greater degree, which translates to the amount of practice they put in," says director Lee Seung-hun. "We hear a lot from overseas teams talking about how their team spirit changed for the better after fielding Korean players."

Kim Hyo-han, the Overwatch coach, makes it clear that Tae-min's practice hours are actually on the lower end of the spectrum.

"A lot of students log 40 or more hours a week."

Beyond gaming itself, what the academy is really trying to do is give competitive gaming the sheen of professionalism, replacing stereotypes about gamers being awkward shut-ins with the kind of culture of sportsmanship and integrity underpinning traditional athletics. Students' in-game conduct is scrutinized, and any kind of unsportsmanlike behavior is swiftly disciplined, says director Lee Seung-hun.

"It's something that we take very seriously, especially since many of our students are still very young."

The lesson here is that pro gamers, too, may someday be iconic public figures whose reach extends far beyond the computer screen. "I want to be a player that is respected and renowned by the world, not just for skill in gaming but other aspects, such as having good character and being humble," says Tae-min.

It's an attitude that's conscious of the skepticism of his parents' generation that's long dogged competitive gaming. But there are already currents of change being felt at the academy.

"Parents who come with middle school- or high school-age students are about half and half in terms of being supportive," says director Lee Seung-hun. "But younger parents are mostly positive because they themselves grew up playing games."

Tae-min's father agrees. "I think it's changing even in my demographic, especially with esports being featured at the Asian Games," he says. "Nowadays, people's reactions are more, 'Oh, that's interesting,' rather than outright disapproval when I tell them about Tae-min's gaming."

Back in the classroom, coach Kim Hyo-han is throwing some hard career questions at Tae-min. Becoming a professional gamer is, as they say here, harder than getting into the top university in the country.

"Isn't it scary that in pursuing what you love, you might find yourself unable to make a living?" Tae-min says with a grin. "It is scary, but I think I can make it happen with the right effort."