US poker professional Greg Merson emerged victorious from a 12-hour final session to claim the World Series of Poker's biggest title and a US$8.5 million first prize.
The win, after 399 hands were dealt, also gave Merson Player of the Year honours at the event in Las Vegas, a 61-event competition that concluded with the US$10,000 buy-in No-Limit Hold'em World Championship, otherwise known as the main event.
"I've played a lot of long cash games in my career, which helps you prepare for something like this, but this whole stage is something you can't ever really prepare for," Merson said.
He placed the champion's gold bracelet, worth US$150,000, on his mother's wrist.
He added: "I couldn't feel better for everyone who I'm sharing this victory with."
The main event was the fifth-largest live poker tournament in history, with a starting field in July of 6,598 entrants.
They played down to nine contestants at the Rio All-Suite Hotel & Casino on July 17 and restarted the competition two days ago.
Merson, 24, of Laurel, Maryland, who attended the local university, was the chip leader heading into the final day of competition, ahead of 26-year-old Jesse Sylvia and 21-year-old Jake Balsiger.
With only Merson and Sylvia remaining after Balsiger was eliminated on the 382nd hand, Sylvia committed all his chips while holding a suited queen-jack.
Merson was holding a king in his hand, which held up after the community cards were revealed - two sixes, a three, a nine and a seven.
Sylvia earned US$5.3 million as runner-up.
Merson also won a US$10,000 buy-in six-handed no-limit hold'em championship at this year's event.