Vinokourov won in a time of six hours 37 minutes and 48 seconds
Kazakhstan's Alexander Vinokourov secured his biggest win since returning from a two-year doping ban with victory in the Liege-Bastogne-Liege classic.
The 2005 winner finished six seconds clear of Russia's Alexandr Kolobnev with Spain's Alejandro Valverde third.
Astana team-mate and Tour de France champion Alberto Contador was 10th.
Australia's Simon Gerrans was the best-placed rider for British-based Team Sky finishing in 12th, with Olympic gold medallist Bradley Wiggins 74th.
Vinokourov, 36, who has always protested his innocence over the 2007 blood doping charge, was defiant in victory.
"It is magnificent. It is a revenge. I dreamed of this," he said.
"I have returned stronger than before and I've shown everybody that 'Vino' is back."
His win came a week after securing the Tour of Trentino in Italy.