Caught in a 'chain' reaction - Schleck wins Tourmalet stage, but unable to shake off Contador

Schleck won Stage 17 to the Col Du Tourmalet, but was unable to take the Yellow Jersey off Alberto Contador (AP Images)

Andy Schleck won Stage 17's ascent up to Col Du Tourmalet, but the victory proved to be a hollow one as he was unable to distance himself from his rival for the Yellow Jersey, Alberto Contador.

Contador arrived at the Tourmalet's summit with Schleck, so the Spanaird still retains his eight-second advantage heading into Saturday's time-trial, which he is widely-regarded as much more of a proficient rider in this discipline.

Schleck attacked from the main bunch 10km from the end, and dispelling the threat of a seven-man breakaway. Not that the SaxoBank rider was all too concerned: his main protagonist was Astana's Contador, who took the lead capitalising on a mechanical fault from Schleck's bike, widely viewed as against race etiquette to profit in such way.

Schleck's tactics may have proved flawed. The 18km ascent up to the largest mountain of this year's Tour at 2015 metres above sea level, saw the Luxembourgeois ahead of Contador throughout the treacherous climb. This meant every time Schleck attacked, Contador could react to it much sooner than if Schleck attacked from behind the Spanaird. However, at the same time, Schleck does not possess the same explosiveness in attacking to break clear of his rivals at steeper mountains.

The 40km time trial is a weakness in Schleck bike riding capabilities. He simply doesn't average as fast a speed compared to Contador. By the end of Saturday, we could see Schleck losing many seconds if not, minutes.

Both are the two best climbers by far of this year's combatants. Samuel Sanchez and Denis Menchov, third and fourth in the General Classification respectively, are over three and a half minutes behind GC leader Contador, having lost around a minute to the fierce rivals.

Friday's stage to Bordeaux is a flat stage favouring a bunch sprint finish, so Saturday's time-trial will be the last opportunity for significant changes to the GC standings, before Sunday's precessional stage to the Champs-Elysses in Paris.