NEW YORK — The defending world champion is a 25-year-old Norwegian who’s been named one of the world’s sexiest men.

Magnus Carlsen is tops in an endurance sport that does not require him to move from his chair.

It’s called chess.

Carlsen, the highest rated player in chess history, again aims to win the World Chess Championship – the most eagerly awaited match in a generation, starting Friday in New York.

Trying to wrest the champion title from Carlsen is the Ukrainian-born Russian grandmaster Sergey Karjakin, who is 26.

The prize purse of $1.1 million will be divided 60-40 between the two men, who are treated like rock stars in their countries.

Carlsen and Karjakin will play in a renovated Manhattan building on the city’s historic 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 the Russian city of Sochi in 2014.

In the United States, organizers face a challenge: How to popularize a sedentary sport with little visible action in a society where most fans favor super-dynamic sports like football, boxing, basketball and baseball.

Still, chess has fervent American fans, including Jay Z, Jude Law, Arnold Schwarzenegger and President Obama.

The International Olympic Committee classifies it as a sport, as do more than 100 countries. It requires not only brain acrobatics but also the physical stamina to sit as long as six hours at a time for three weeks.

Electronic versions of the game register about 1 billion downloads a year of hundreds of apps, says Ilya Merenzon, the Moscow-based chief executive officer of Agony Limited, which owns the marketing rights to the World Chess brand that controls tournaments leading to the championship.

There are an estimated 600 million players worldwide, Merenzon says.

By contrast with 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 ever, and Carlsen was a grandmaster at 13.

Carlsen has cashed in through sponsorships, his own chess app and modeling for ads.

He also was selected by Cosmopolitan magazine as one of the “sexiest men of 2013.” Since then, he’s also been the world’s No. 1 player.