Evenepoel powers to Vuelta stage three win and takes red jersey
The Belgian Soudal-QuickStep rider fell after crossing the finish line, colliding with a spectator amid a throng of people and continued his celebrations with a bleeding forehead.
The crash continued a run of bad luck at the start of this year's race which began with a thunderstorm before the opening stage, a team time trial that finished in near darkness.
The second stage was partially suspended, with general classification times taken nine kilometres before the finish because of slippy and dangerous conditions.
"Some things (about) safety," said Evenepoel. "(The crash) was only 50 metres after the finish line, and it's the third day in a row (there have been problems)."
The 23-year-old's afternoon was otherwise perfect, crossing the line first on Monday after the race headed away from Barcelona and into the Pyrenees, ending up in Andorra after 158.5 kilometres for a summit finale.
Evenepoel dominated the finish in Arinsal, crossing the line a second ahead of back-to-back Tour de France winner Vingegaard, whose Jumbo-Visma team-mate and thee-time Vuelta winner and reigning Giro d'Italia champion Primoz Roglic was fourth, behind young Spaniard Juan Ayuso in third.
Should Vingegaard or Roglic triumph in the Vuelta, Jumbo-Visma would become the first team to win all three men's grand tours in a season in the modern era.
"I felt super good on the final climb with a long but very strong sprint so I'm super happy with this stage win," said Evenepoel.
"I felt I had a big punch still in my legs. I'm gonna enjoy the red jersey. It's a beautiful victory here in Andorra, at high altitude.
"It shows my preparation was good and that I'm ready for the next three weeks."
The Belgian is five seconds ahead of Movistar's Spanish rider Enric Mas overall, while Frenchman Lenny Martinez is third. 11 seconds behind the leader.
Hilly stage four on Tuesday takes riders185 kilometres from Andorra to Tarragona, with a sprint finish likely.
This is the 78th edition of the race, which ends in Madrid on September 17 after 21 stages and 3,153.8 kilometres.