The final mountain stage of the 2010 Tour de France was already designed to be incredibly challenging, with 3 high mountain passes in the Pyrenees, each one harder than the last. Add in the fact that the top two riders in the race were separated by only 8 seconds at the start of the day, and Stage 17 became one of the hardest rides the Tour has ever seen.

As expected, Team Saxo Bank put all their cards on the table riding in support of Andy Schleck, who did his best to attack Alberto Contador in an effort to reclaim the yellow jersey. Launching Andy into that attack on the Tourmalet, his team mate Chris Anker Sorensen set a new record for sustained power output, cranking out 6.6 watts per kilogram for 10 minutes before peeling off - and watching Andy ride even harder from there as he took off towards the summit finish with Contador on his wheel.

In his analysis of the today's power file, Hunter Allen explains how Chris timed his effort perfectly as part of the overall team strategy to help Andy make a bid to reclaim the yellow jersey before Saturday's time trial. "It was Team Saxo Bank's strategy to go all out and make the race as hard as possible today, and Chris was definitely helping to make that happen. He spent more time in his threshold zone today than any other day in this year's Tour de France."

"On the final climb of the Tourmalet, Chris was the second rider in line to lead out Andy Schleck. Fabian Cancellara was having one of his best mountain days ever and started the lead out at the front on Tourmalet. When he swung off, Chris took over and knocked out his best 10 minutes of the Tour at 415 watts or 6.6 watts per kilogram! His effort came to an end when Barredo made the first attack and then Andy Schleck attacked and only Contador could stay with him."

In the brutal duel that ensued up the final kilometers of the climb, we can only imagine how many watts Andy and Alberto were cranking out as they battled through the fog to the finish line. Each rider eyed the other warily, attempting attacks that never quite went anywhere as in the end Alberto stayed glued to Andy's wheel and they crossed the finish line with the same time, evenly matched on the climb.

Compare today's power data to the other stages of the Tour, check out a video to see Dirk Friel explain more about power meters, and stay tuned to Roadcycling.com for the final showdown in the time trial on Saturday!

Want access to the same training diary and training data analysis tools used by Chris Anker Sorensen, Andy Schleck, Fabian Cancellara and other Team Saxo Bank riders in the Tour de France? Sign up for your own training diary now!