Kenya's Eliud Kipchoge underlined his credentials as the undisputed king of the marathon with a dominant run to retain his Olympic title on the streets of Sapporo on Sunday.
The world record holder clocked 2hr 08min 38sec to win gold, becoming only the third man to win consecutive marathon titles.
Abdi Nageeye of the Netherlands claimed silver in 2:09.58, just ahead of Belgium's Bashir Abdi in the final event of the athletics programme at the Tokyo Games.
Kipchoge's victory margin of 1min 20sec was the biggest since Frank Shorter's win in the 1972 Munich Games.
The 36-year-old's triumph, his 13th win in the 15 marathons he has raced since 2013, came a day after teammate Peres Jepchirchir secured back-to-back women's Olympic marathon titles for Kenya's women.
"I think I have fulfilled the legacy by winning the marathon for the second time, back-to-back. I hope now to help inspire the next generation," Kipchoge said.
"It means a lot for me, especially at this time. It was really hard last year, it (Olympic Games) was postponed. I am happy for the local organising committee who made this race happen. It is a sign that shows the world we are heading in the right direction - we are on the right transition to a normal life."
World Athletics president Sebastian Coe called Kipchoge "a hero", saying his ground-breaking sub-2hr marathon run in 2019 - in a specially arranged race that does not count for record purposes - "a massive moment in our sport".
"He's a hero to millions and millions of people," said Coe, who won two 1500m Olympic golds for Britain.
"You only have to see the emotional appeal he has. He thoroughly deserves it."
Unlike in Tokyo, where stringent Covid-19 restrictions have forced the Games behind closed doors, thousands of spectators lined the streets of Sapporo, a city that lies more than 800 kilometres (500 miles) north of the capital.
The organisers' decision to move the race backfired, however, with unseasonably hot and humid temperatures making for gruelling conditions for the runners.
"The Olympic dream is a special dream," said Kipchoge. "For every athlete here, it has taken a lifetime of preparation to get to this point.
"Today I lived my Olympic dream. I always say that sport is like life, whereby you can win and lose. But today was a day where I won and get to say I successfully defended my Olympic title."