While France's Sandy Casar claimed stage victory in St. Jean de Maurienne, Schleck snatched the yellow jersey from Evans, who finished more than eight minutes off the pace after collapsing in the last big climb of the Alps, the Col de la Madeleine.

Casar won the 204.5-km ninth stage from Morzine on Tuesday. Spain's Luis Leon Sanchez was second and Italy's Damiano Cunego came home third.

Riding side by side with Contador during the last 30 kilometers, Schleck opened up a 41 second lead over the defending champion as the Tour neared the halfway point.

The Spanish maestro and his Luxembourg rival, who were first and second last year, left third-placed Samuel Sanchez trailing by 2:45.

The first unrated mountain pass in this Tour, the 25-km long Col de La Madeleine, proved decisive.

Two days after being involved in a crash in which he suffered hip and thigh injuries, Australia's Evans became the latest big name to slip out of contention after cracking with eight kilometers to go to the summit.

He broke down in tears after struggling over the line in 42nd place, a result which dropped left him nosediving from first to 18th in the overall standings.

On Sunday, seven-times champion Lance Armstrong's victory hopes were dashed when he crashed during the eighth stage.

With seven kilometers to go, Olympic champion Sanchez was the only rider able to follow last year's top two finishers.

All the other Tour contenders — Denis Menchov, his Dutch team mate Robert Gesink and American Levi Leipheimer, followed by a group including Armstrong and Giro d'Italia winner Ivan Basso and further down Czech Roman Kreuziger and Briton Bradley Wiggins — failed to keep pace.

Schleck tried to attack Contador three times unsuccessfully near the summit before the two started chatting with each other, deciding to join forces to eliminate their rivals and postpone their own personal battle for the top spot.

Casar beat Spain's Luis Leon Sanchez and Italy's Damiano Cunego for the stage honors. The three were what remained of a 12-man breakaway launched from the gun.

The Tour will leave the Alps after a 179-kms 10th stage between Chambery and Gap on Wednesday.
 

With Evans now out of the picture, Contador has only Schleck to worry about.

The defending champion lies second in the overall standings, 41 seconds behind Schleck, the only one able to compete with the Spaniard. But the Luxembourg rider is likely to lose some ground in the final time trial, a 52-km effort that suits Contador.

"My rival is Andy. I now have to stay in his wheel," Contador told reporters after dominating all his rivals apart from Schleck in Tuesday's ninth stage.

Schleck could not agree more.

"Now it's between Alberto and me. There is only one rider to focus on, it's Contador," the Saxo Bank rider told a news conference.

Contador and Schleck finished sixth and seventh respectively on Tuesday, with American Levi Leipheimer, Dutchman Robert Gesink and Russian Denis Menchov over two minutes behind.

Italy's Ivan Basso and Czech Roman Kreuziger were almost three minutes off the pace.

All were dropped in the punishing ascent to the Col de la Madeleine, a 25.5-km climb at an average gradient of 6.2 percent following Astana's perfect team work.

"It was a good day, obviously. We made big differences, more than we expected," Contador explained after a quick shower in his team's bus.
 

"In the Col de la Madeleine, everybody gave everything. We saw that Cadel Evans was isolated," Astana manager Yvon Sanquer told Reuters.

Evans is now 18th overall, seven minutes 47 seconds off the pace.

"We had enough riders to increase the pace and make it harder for our rivals as some of them were showing signs of weakness," Sanquer added.

Italian Paolo Tiralongo and Spain's Daniel Navarro swapped at the front of the favorites' group until Contador and Schleck found themselves alone up front.

Astana also had Alexandre Vinokourov sent chasing a group of breakaway riders, forcing the other teams to work hard to try and catch the Kazakh.

"There was a part of instinct (in these moves) and a part of calculation," said Sanquer.

With the common interest of eliminating their rivals, Schleck and Contador then worked together to gain more time.

"There were four little attacks but then we had an agreement," said Contador.

After only nine stages and still the Pyrenees to come, third-placed Samuel Sanchez is already trailing Schleck by 2:45.

Menchov is fourth, 2:58 off the pace, and Leipheimer lies sixth, 3:59 behind.

Giro champion Basso, Kreuziger, 2008 Tour winner Carlos Sastre and Briton Bradley Wiggins all lie more than five minutes adrift.

"It's gonna be a very tough contest (between Contador and Schleck). They collaborated today but the time will come when there will be no gifts," said Sanquer.