Magnus Carlsen, the highest-rated player in history, is beginning the defence of his world title in the most eagerly-awaited match in a generation as the World Chess Championship begins on Friday in New York.
Carlsen, a 25-year-old Norwegian, has been named one of the world's sexiest men.
Trying to wrest the title from him is the 26-year-old Ukrainian-born Russian grandmaster Sergey Karjakin.
The prize purse of 1.1 million US dollars (£870,300) will be divided 60-40 between the men, who are treated like rock stars in their countries.
Carlsen and Karjakin will play in a renovated building on the historic Manhattan waterfront, near Wall Street and the Brooklyn Bridge.
The championship has returned to the United States for the first time in 21 years; the last one was in Sochi, Russia, in 2014.
In the US, organisers face a challenge - how to popularise a sedentary sport with little visible action in a society where most fans favour dynamic sports like football, boxing, basketball and baseball.
Still, chess has its fervent American fans, including Jay Z, Arnold Schwarzenegger and outgoing president Barack Obama.
The International Olympic Committee recognises the World Chess Federation, which governs championship-linked matches, as a sports entity. It requires not only brain acrobatics but also the physical stamina to sit as long as six hours at a time for three weeks.
The battle pits figures of medieval warriors, kings, queens, bishops and knights against each other in ever-changing plots as dramatic as Game Of Thrones.
About one billion downloads have been tracked to apps offering electronic versions of the game, says Ilya Merenzon, the Moscow-based chief executive officer of Agon Ltd, which owns the marketing and commercial rights to the World Chess brand for the championships and the qualifying games leading up to it.
There are an estimated 600 million players worldwide, Merenzon says.
In contrast to the glitzy, high-tech championship, chess enthusiasts can be found playing in hundreds of New York outdoor public spaces, such as Central Park. Some of these urban street players are homeless.
Karjakin was 12 when he became the youngest grandmaster, and Carlsen was a grandmaster at 13.
"When I was young, I was used to winning games in a very aggressive style, and I would attack all the time and I was used to my opponents cracking," Carlsen said. "But when I got to the highest level, then people defended better, so now I'm more pragmatic. Whatever risks I take, I try to control the game."
Carlsen has cashed in through sponsorships, his own chess app and modelling for ads. He appeared in G-Star Raw's spring/summer fashion ad campaign along with actress and model Lily Cole.
He also was selected by Cosmopolitan magazine as one of the sexiest men of 2013. Since then, he has also been the world's number one player.
All 600 seats for Friday's inaugural game were sold out, starting at 75 dollars (£60) apiece. Two games are played on consecutive days, followed by a one-day break, for a total of 12 games.
Tens of millions of fans are expected to follow live online, free of charge through the worldchess.com website and affiliate partners. In addition, pay-per-view buys the game in virtual reality, allowing fans to experience the game as if they were there by wearing special goggles.
For years, chess seemed to be played in a bubble, far from mainstream media.
This week, New York will host the first championship with two grandmasters of the smartphone generation - "a battle of two of the finest minds on the planet", Merenzon says. "Our goal is to make chess a pop culture event."