Assen, Netherlands - Swiss Olympic champion Fabian Cancellara on Saturday won the Tour of Spain prologue in a time of 5 minutes 20 seconds.

The Saxo-Bank rider, who also won the opening time trial at this year's Tour de France, edged out Belgium's Tom Boonen by nine seconds and American Tyler Farrar by 12 to take an early lead in this year's Vuelta.

"Before the start of the race I would not have placed a bet on me. I gave it my best and now I am really happy," the Swiss said.

Russian Alexander Vinokourov, who has only just returned to cycling after a two-year doping ban, finished in seventh place 18 seconds behind Cancellara.

Two other controversial riders, Italian Ivan Basso and Spain's Alejandro Valverde also finished 18 seconds behind.

Sunday's second stage takes the riders over 202 kilometres from Assen to Emmen in the Netherlands. (dpa)