Oscar Pereiro reclaimed the race leader's yellow jersey on stage 16 of the Tour de France after American rider Floyd Landis fell apart under a succession of attacks from his rivals for overall victory.

Pereiro has a provisional overall lead of one minute, 50 seconds over fellow Spaniard Carlos Sastre whose late attack unsettled Landis and finally eliminated the American from realistic contention for overall honours.

German rider Andreas Kloden is third overall, 2mins 29secs behind Pereiro who is now closing in on overall victory in the first Tour of the post-Lance Armstrong era.

Honours on the day went to Denmark's Michael Rasmussen who took the red polka-dot jersey for the "king of the mountains" - the title he won last year - as he claimed a stage victory from the front after a marathon breakaway.

However, it was the near-collapse of Landis that was the main talking point as the American ran out of energy in the closing 15km of the 182km stage and surrendered not only his hold on the leader's yellow jersey but any realistic chance of winning this year's race as he trailed in over ten minutes behind the Dane in 23rd.

Landis had withstood several attacks from his rivals but when Sastre produced a turn of speed he could not live with the Spaniard.

Sastre finished second behind Rasmussen on the day with his excellent finish to the day but it was not enough to win him the yellow jersey with Pereiro finishing only 13 seconds behind his compatriot.

Rasmussen once again proved to be at home in the Alps, maintaining his rhythm despite being out on his own from the sixth kilometre.

It was a virtuoso display by the Dane on the gruelling Alpine stage which included two climbs so steep that they can not be categorised.

One climb, the Col du Galibier, was the highest point of the 2006 Tour some 2646m (8,681 feet) above sea level.

At one point the Dane had held an 8mins 29secs advantage over his closest pursuers although the gap started to come down with American Levi Leipheimer and Slovenian Tadej Valjavec reducing arrears as the day went on.

With 15km to run, Leipheimer had reduced the lead to four minutes and 10 seconds.

Landis, who had reclaimed the leader's yellow jersey from Oscar Pereiro, was shadowed by his principal rivals for overall victory by Pereiro and Cyril Dessel in the yellow jersey group.

The American, now riding for the Phonak team, was attacked by Denis Menchov in the closing kilometres but the leaders reined in the Russian without too many problems.