REUTERS - Overall leader Alberto Contador proved he was simply the best rider in the Tour de France by winning Thursday's 40.5-km individual time trial around the lake of Annecy.

The Spaniard, peerless in the mountains, was also the fastest of the peloton against the clock on the 18th stage with a time of 48 minutes 30 seconds.

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The 2007 Tour champion beat Olympic gold medallist Fabian Cancellara by three seconds and Russia's Mikhail Ignatiev by 15.

The main disappointment of the day came from American Lance Armstrong, who started fast but was unable to maintain the pace and finished 16th in a stage which seemed to suit his qualities.

The seven-times champion's performance, 1:30 off the pace, was enough to oust Frank Schleck of Luxembourg from third spot overall.

Frank Schleck's brother Andy limited the damage to retain his second place, 4:11 behind Contador.

Contador's team mate Armstrong was 5:25 adrift while Briton Bradley Wiggins was fourth, 5:36 off the pace and two seconds ahead of Germany's Andreas Kloeden.