When Olympic organisers in 2019 suddenly decided to move the venue for the race walk and marathon about 800km north of Tokyo to Sapporo, their only goal was to escape the scorching summer heat in the capital.
But on Thursday, the men competing in the 20km race walk poured water over their steaming bodies and gulped down water as temperatures in the biggest city on the country's northernmost island reached a punishing 33 degrees Celsius (91.4°F).
Passers-by hid under black, heat-reflecting umbrellas, dogs had their tongues hanging out to cool themselves, and even the most ardent spectators along the course sought patches of shade as they watched the athletes.
"It's hot up here, we came up here because we thought it would be cool. It's not - it's not much cooler than Tokyo," said Tricia Adkins, a U.S. citizen living in Japan who had come to Sapporo to watch the race.
In Tokyo, organisers have deployed a host of tools - from mist-spraying stations to cooling vests to AI gadgets that warn of heat-stroke risk - to beat the heat while handing out salt tablets and ice cream to volunteers.
More than two dozen people involved in the organisation of the Olympics have suffered heat-related illness, although all had mild symptoms, the organisers have said.
Italy's Massimo Stano won the race walk on Thursday, pulling ahead of the pack in the final stages to claim his country's third ever gold medal in the event.
"I thought we decided to hold the marathon because it's cool here. But it's hot and everyone is tired. It's difficult for the athletes due to the risk of heatstroke," said Mariko Baba, a 50-year-old resident of Sapporo. "But I hope they’ll do their best."