Greg Van Avermaet of Belgium captured gold for Belgium in the men's cycling road race at the Olympics on Saturday.
Van Amermaet, 31, beat Denmark's Jakob Fuglsang in a sprint finish, with Rafal Majky of Poland taking bronze.
Italy's Vincenzo Nibali and Colombia's Sergio Henao crashed while in a leading group with Majky on the final descent with some 10 kilometres remaining.
Britain's Geraint Thomas, who had fallen away from the leading trio, also crashed on the same descent.
Majky was left out on his own and was 25 seconds ahead of the chasing group with 5.5 kilometres of the 237km race to go.
Van Avermaet and Fuglsang closed up on a tiring Majky with some 1.3 kilometres remaining, and the Belgian was the stronger over the final metres along the Copacabana with Majky unable to challenge.
"I am so happy for gold. Everyone said all week it was for everyone else," Van Avermaet said.
"When I saw the crash I was confused about how many riders were still up the road. I was working with Fuglsang, and we saw Majka. We knew it was possible. I knew I had to hang on."
Majka said: "I don't know how I did not crash but somehow I made it through. In the end I had such hard cramps in my legs I could barely pedal. When the others caught me I knew that it was impossible to win."
Tour de France winner Christopher Froome of Britain had to settle for 12th, some three minutes off the pace, on what was arguably the toughest road race course at the Olympics.
There was brief scare earlier in the race when police conducted a controlled explosion at an unattended backback near the finish area. But normality soon returned as the pack contained clothes and other goods.