Controversy is swirling around Alberto Contador's decision to attack at the end of the final climb today while Andy Schleck was struggling with his chain. After so much hard work from both Andy and his team mates, losing the yellow jersey to an unlucky mechanical failure and an attack of dubious character has without a doubt left a bad taste in many people's mouths.

Before the trouble with the chain began, Andy had been launched into a break that included just 5 of the top riders by his team mate Chris Anker Sorensen, who set such a fast pace at the beginning of the climb that only 15 riders were left before Andy set out on his own. Chris pumped out 6 watts per kilo for over 20 minutes on this effort, so just imagine what Andy must have been doing when he rode away from Chris!

Just 3km from the top of the climb, Andy began an attack that was designed to leave Contador and the other 3 riders behind - but unfortunately backfired when he dropped his chain just as the others launched a counter-attack, leaving Andy frantically struggling to repair the damage while Contador and the rest rode ahead over the summit.

Attacking the yellow jersey during a mechanical failure is generally considered poor Tour de France etiquette, especially if the one doing the attacking happens to be in second place. However, there has been some debate over whether or not Contador realized what had happened to Andy, as well as the question of whether or not the other riders would have stopped and waited with Contador since the race for the summit was really on at that point. Check out Roadcycling.com's view here.

Whether or not Contador should have attacked, the new yellow jersey rider will need to watch out for Andy and the rest of Team Saxo Bank during tomorrow's stage, which promises to be one of the toughest in the Tour. It crosses all four of the most famous passes in the Pyrénées - the Cat. 1 Peyresourde and Aspin, and the hors categorie Tourmalet and Aubisque - and includes 15,000 feet of actual climbing.

If Andy can take the jersey back before the final rest day on Wednesday, he will have just one more day of climbing to defend it before the last showdown in the time trial on Saturday, where Contador is almost certain to finish ahead Andy. How much time Andy would need to gain against Contador before the time trial is anyone's guess, but without at least a small cushion his hopes of finishing at the top of the podium in Paris may be over for this year.

Stay tuned during these final days of racing for more commentary and analysis!

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