The 29-year-old Londoner, who had slipped out of the top three into sixth after yesterday's stage up the Alps, was the fastest through checkpoint three, at Cote de Bluffy 28.5km out, but he could not maintain that pace and faded badly towards the end.

 

He at least overtook Andreas Kloden and Frank Schleck, the winner of stage 17 who is more of a climber than a time-trial specialist, and is just 11 seconds behind Lance Armstrong with three days left before the race finishes in Paris on Sunday.

 

Alberto Contador strengthened his position at the top of the general classification by powering to victory in today's individual time trial in stage 18 of the Tour.

 

The Spaniard, who rides for Astana, was three seconds quicker than Fabian Cancellara today and now has a lead of 4min 11sec over nearest challenger Andy Schleck, of Luxembourg.

 

Having proved in the Alps he is the strongest in the mountains, the 2007 champion showed today, on the 40.5 kilometres jaunt round Lake Annecy, that he was the best against the clock and looks in prime shape to claim his second Tour title.

 

The podium positions remain up for grabs, although Andy Schleck will be difficult to displace after consolidating his second place today despite finishing 21st in the time trial.

 

Armstrong finished 16th today while Garmin Slipstream's Wiggins, who faded in the final 5km after starting the time trial superbly, came home a place behind fellow Briton and team-mate David Millar.

 

The biggest loser was Saxo Bank's Frank Schleck, who drops from third to sixth.

 

The day belonged to Contador, who was the fastest at all the main splits, and posted a time of 48:30.

 

The 27-year-old said: "It's been a great day.

 

"Winning a time trial in the Tour de France is really special.

 

"And I beat all the specialists.

 

"We are near the end but there are still three days left.

 

"I must be careful."