Kenya's Eliud Kipchoge underlined his credentials as the undisputed king of the marathon with a totally 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," he added of winning his second gold medal.
"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", calling 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."
SAPPORO HEAT
Unlike in Tokyo, where stringent Covid-19 restrictions have forced the Games behind closed doors, thousands of spectators lined the streets of Sapporo, the host city of the 1972 Winter Olympics that lies more than 800 kilometres (500 miles) north of the capital.
The organisers' decision to move the race to the city, however, backfired, with unseasonably hot and humid temperatures there making for gruelling conditions for the runners.
Sunday's race saw 106 runners representing 45 countries and the Olympic Refugee Team set off from Odori Park in the heart of Sapporo in temperatures of around 27 degrees Celsius (81 degrees Fahrenheit) and a stamina-sapping 80 per cent humidity.
A large lead group of about 50 runners, including Kipchoge, defending world champion Lelisa Desisa of Ethiopia and Rio bronze medallist Galen Rupp of the United States went through 10km in 30min 53sec.
Kipchoge had teammates Lawrence Cherono and Amos Kipruto beside him as running partners.
Two early casualties of note were Uganda's Stephen Kiprotich, who was gold medallist at the 2012 London Games, and Ethiopian Shura Kitata Tola, winner of last year's London Marathon, in which Kipchoge finished eighth in just his second blip in his marathon-racing career.
Daniel do Nascimento of Brazil also dropped out with cramp as Kipchoge led an 11-strong group through the 1:30 mark.
The Kenyan then kicked away on a solo breakaway as the pack split further, opening up a 27-second lead through 35 kilometres (1:46.59).
Cherono, Ayad Lamdassem of Spain, Abdi and fellow Somali-born Nageeye were left battling among themselves in the chasing pack, as 30 of the field failed to finish.
"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."