The epic length and difficulty of the world championship road races in the hills around Kigali this weekend favour Tadej Pogacar for the men and Pauline Ferrand-Prevot in the women's race.
The pair are the reigning Tour de France champions and should thrive on the 1 500m altitude and the relentless short but steep climbs on the one-day race.
The men's race on Sunday is extremely long at 267.5km and includes 33 climbs, over 15 loops and one longer, even harder loop with an extra cobbled climb.
Pogacar said the humidity and altitude were potentially decisive factors.
"We're quite high here and you can feel it, not so much walking around, but on the bike. Also, the air quality here in the city is not the best," he said
"You feel the difference."
The humiliation of being overtaken on the same roads on the 42km time trial by Remco Evenepoel a week ago adds extra motivation for Pogacar, but also begs questions over his form.
"I didn't catch my rhythm, I didn't catch my legs," he said Thursday. "I don't have any issues now this week, I feel ready."
Evenepoel, who caught the 27-year-old Slovenian after starting 2min 30sec later, won both the time trial and road race Olympic titles in 2024. If he emulates that feat Sunday he would be the first rider to win both world titles the same year.
There is also a cobbled climb on the routes for both the men and women as a nod to the Belgian one-day classics.
Another of the favourites, Britain's mountain bike Olympic champion Tom Pidcock, said the course suited Pogacar because of its resemblance to the hilly Tour of Flanders which the Slovernian has won twice and Evenepoel has never entered.
"This cobbled climb is like the 'Vieux Quaremont', perfect for Tadej," said Pidcock who came third overall at this month's Vuelta a Espana.
MOMENTUM
Olympic mountain bike and Tour de France champion Ferrand-Prevot goes into Saturday's 167km women's race in fearsome form both physically and mentally.
"I feel very good, unlike the Olympics where I was tired afterwards. Now I'm continuing my momentum," said the 33-year-old who produced a series of dominant climbs at the Tour.
"I have a lot of experience at altitude. I did a three-week altitude training camp to prepare," she said, describing the course as punchy.
"The course is up and down all the way. I was expecting it to be more difficult but it suits me," she said.
These are the first cycling worlds to be held in Africa, with Kigali providing wide roads with quality surfaces.
The champions are awarded a rainbow jersey that they wear for the year, a much coveted prize in what is essentially an amateur race with riders representing their nation rather than a professional team.
Along with Evenepoel in the men's time-trial, Swiss rider Marlen Reusser won the women's race while Australia won the mixed team relay on Wednesday.