Judgement day has arrived for Cadel Evans.

He probably can't win the Tour de France in tonight's gruelling final mountain stage, concluding on the famed Alpe d'Huez peak, but he can certainly lose it.

Alpe d'Huez is the most famous of all the mountains in the Tour. A 13.8km climb at a gradient of 7.9 per cent, with 21 hairpin bends, each named after the individual stage winners. Only the legendary names conquer Alpe d'Huez: Fausto Coppi, Bernard Hinault, Miguel Indurain and Lance Armstrong.

If Evans can add his name to the list, he will be the favourite to claim the title in Paris on Sunday. If Alpe d'Huez takes a hold of Evans, his dream of becoming the first Australian to win the Tour de France will be dashed after the dramatic events of the 18th stage overnight.

Evans was the highest placed general classification contender going into the stage, only to be hit by a brutal one-two punch from brothers Andy and Frank Schleck of Luxembourg.

Leopard-Trek proved to be the strongest team in the tour, both physically and tactically, sending Joost Posthuma and Maxime Monfort into early breakaways, and lay the foundations for Andy Schleck to launch the deciding breakaway, which saw him take stage honours.

Schleck caught Evans, Alberto Contador and the other yellow jersey contenders by surprise, as he launched an audacious bid for victory, by leaping from the pack with more than 60km left in the stage.

What awaited for Schleck was nearly two hours of climbing solo, including the highest finish in Tour de France history, at the summit of the Col du Galibier. But his efforts were helped dramatically as he reached teammates Posthuma and Monfort, receiving valuable respite, before continuing on towards victory.

Schleck won the stage by 2min 07 seconds from brother Frank, with Evans fighting valiantly to finish third. Andy Schleck is now just 15 seconds behind leader Thomas Voeckler, and is expected to be in the leader's yellow jersey after tonight's stage.

Speaking on his surprise attack after crossing the line, Schleck said: "I don't want to finish fourth in Paris, and I said to myself 'I'm going to risk everything, it'll work or it'll fail'. "That's the way I am, I'm not afraid of losing. And if my legs were hurting out in front I knew the others would be hurting to catch me up."

Frank Schleck is in third overall, 1min 08 seconds behind Voeckler, with Evans just a further four seconds back. Defending champion Contador was the biggest surprise from the stage, losing 3min 15 seconds to Schleck, and now seems out of the race for this year's title.

Voeckler, not a noted climber, has fought defiantely to wear the yellow jersey for the last ten stages. He has been an inspiration and has truly honoured the history of the maillot jaune.

Tonight's short but epic 109km stage to Alpe d'Huez goes over three daunting climbs, including a second meeting with the Galibier, only this time from the hardest side.

For Evans, the stage is all about staying with the Schleck brothers, who have proven to be the strongest riders in the race. Where Evans does have an advantage will be in the following stage, the 42km time-trial around Grenoble.

But Andy in particular, could be driven by the prestige and honour of the famed yellow jersey.