The world's top cyclists are used to being put through the wringer, but even they seemed shocked the Olympic road race, in which only 65 of the day's 144 starters made it to the finish.
The 237.5km course had been touted as the most difficult in Olympic history, and it certainly lived to the hype.
Numerous crashes caused many riders to retire, including Vincenzo Nibali (Italy) and Sergio Henao (Colombia), both of whom seemed in good positions to claim a medal. Britain's Geraint Thomas also crashed out of contention but finished the race.
Instead, Greg Van Avermaet (Belgium), Jakob Fuglsang (Denmark) and Rafal Majka (Poland) formed a three-man group racing for the win, with the Belgian coming out on top to claim gold.
For those without the salve of a medal, however, the race was a painful experience.
"It was the most difficult day on the bike I've had in my career," said Ireland's Dan Martin, who finished 13th, 2-58 behind Van Avermaet. "It was just a brutal, brutal day.
"I was hoping to race for the medals, but I wasn't on a super, super day. I was still in contention until the end, so I have to be satisfied. I just lacked that little bit on the final climb. It was a strange old race."
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A day packed with incident was at time difficult to follow even for spectators, so it was no wonder that the participants found it challenging.
"It was anarchy out there," said Brent Bookwalter (USA), who finished 16th. "Everything happened. People crashing, flatting, getting gapped out in the wind. It was a very hard day."
Although medals are awarded to individuals, team-members still work to support their leaders. For Michal Kwiatkowski, the aim was to get his Polish teammate Majka into a strong position. He finished 62nd, but his team leader claimed bronze.
"The cramps were bad," said Kwiatkowski of the long break he was involved in. "I was done. But that was always the plan, actually, for me to get ahead and work for Rafa. So it was good – I was able to do some good work for him, and I think that helped in the end."
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There is something special about the Olympics, of course, and Joaquim Rodriguez (Spain), in his final season as a pro, was happy just to be involved.
"It was a hard, complicated race," he said. "I gave it my all. I would have liked to have a medal, but to leave the Olympics after such a fantastic day of racing leaves me with a sweet taste."
