Marcus Burghardt profited from a transitional day in the Tour de France to escape to victory on the 18th stage from Bourg d'Oisans to St Etienne.

Burghardt caught solo escapee Carlos Barredo 94km into the 197km stage and held off the Spaniard's late dash in the closing metres to secure Team Columbia's fifth stage win of the Tour.

The 25-year-old German is best remembered for being knocked off his bike by a dog in last year's event, but he had the chance to change all that with the freedom granted to him on an uneventful day.

Burghardt's win puts the gloss on a fine Tour for the Columbia team, who won four perfectly-executed bunch sprints courtesy of Mark Cavendish earlier in the race.

After three tough days in the Alps, the main contenders were content to conserve their energy for the crucial time-trial from Cerilly to St Amand Montrond on Saturday.

Carlos Sastre came through unscathed and retains his 84-second lead over CSC colleague Frank Schleck.

Sastre, hoping to become the third consecutive Spaniard to win the Tour de France after Oscar Pereiro and Alberto Contador, must decide whether to try and gain more time on Cadel Evans in Friday's flat stage from Roanne to Montlucon.

Sastre still heads Evans by 94 seconds in the race for outright victory, but with a long, 53km stage against the clock to come.

The Australian is a vastly superior time-triallist, though Sastre has made genuine attempts to improve his aerodynamic position in recent years.

In the shorter 29.5km time-trial at Cholet in stage four, Sastre still conceded 70 seconds to Evans.

The situation is eerily similar to 1989, when Greg LeMond turned a 50-second deficit on Laurent Fignon into an eight-second win in the closing time-trial from Versailles to Paris.

The only major gains in Thursday's Massif Central stage were made by Andy Schleck and Roman Kreuziger, who came in 11 seconds ahead of the groupe maillot jaune and edged closer to the top 10.

Burghardt shrugged off Barredo's attempts to toy with him on the Cote de Sorbiers and then again when they reached St Etienne.

"I tried to take charge on other stages, but without success," Burghardt told letour.fr.

"So when I saw Barredo had gone, I wanted to go after him.

"When I approached him, we exchanged a few words, and Carlos told me that he would not take over, because he knew that I would be very quick when it came to the sprint.

"I knew that Barredo was going to try and attack at the end. He tried several times, and each time I responded.

"The sprint became very tactical. I have good experience of those sort of sprints from track cycling, and I justifiably trained for a long time on the track.

"I think that served me well in the end."

Further back, Damiano Cunego, Philippe Gilbert and Alexandre Botcharov suffered a nasty crash 33km into the stage.

Medics applied treatment to Cunego's chin and he rejoined in a group detached from the yellow jersey.

In the race for the other jerseys, Oscar Freire made more gains on sprint rival Thor Hushovd, giving him a 49-point lead in the points competition with the traditional sprint up the Champs-Elysees to come.

Barring accident or withdrawal, Bernhard Kohl will be the first Austrian to win the polka dot jersey for the King of the Mountains competition.

The prospect of a genuine opponent for Kohl ended after injury to 2007 winner Juan Mauricio Soler, and the withdrawal of Saunier Duval-Scott climbers Riccardo Ricco, David de la Fuente, Leonardo Piepoli and Juan Jose Cobo.

During the stage, French customs officials searched a car belonging to Johnny Schleck, the father of Frank and Andy.

The inspection, which found nothing untoward, was part of a series of random checks near Grenoble.

Leading final positions after Stage 18 (Bourg d'Oisans - Saint Etienne, 196.5km): 1 Marcus Burghardt (Ger) Team Columbia 4hrs 30mins 21secs, 2 Carlos Barredo Llamazales (Spa) Quick Step at same time, 3 Romain Feillu (Fra) Agritubel at 3.33, 4 Christophe Le Mevel (Fra) Credit Agricole at same time, 5 Mikel Astarloza Chaurreau (Spa) Euskaltel - Euskadi at 3.35, 6 Samuel Dumoulin (Fra) Cofidis - Le Credit par Telephone at 6.39, 7 Cyril Dessel (Fra) AG2R La Mondiale at same time, 8 Roman Kreuziger (Cze) Liquigas at same time, 9 Leif Hoste (Bel) Silence - Lotto at same time, 10 Andy Schleck (Lux) Team CSC - Saxo Bank at same time, 11 Oscar Freire Gomez (Spa) Rabobank at 6.50, 12 Erik Zabel (Ger) Team Milram at same time, 13 Thor Hushovd (Nor) Credit Agricole at same time, 14 Leonardo Duque (Col) Cofidis - Le Credit par Telephone at same time, 15 Filippo Pozzato (Ita) Liquigas at same time, 16 Robert Hunter (RSA) Barloworld at same time, 17 Steven De Jongh (Ned) Quick Step at same time, 18 Alessandro Ballan (Ita) Lampre at same time, 19 Christophe Riblon (Fra) AG2R La Mondiale at same time, 20 Sven Krauss (Ger) Gerolsteiner at same time

Selected Others: 48 David Millar (Gbr) Team Garmin-Chipotle p/b H30 4hrs 37mins 11secs

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