Daniel Lloyd of Team IG Sigma Sport checked out the 53.5km Stage 19 time-trial from Bonneval to Chartres, the last opportunity for the riders to make a move in the general classification.

Even with Bradley Wiggins apparently all but crowned this year's maillot jaune, there's still scope for plenty of changes, with the riders needing to navigate a complex, technical TT course.

We'll find out on Saturday: coverage of what could prove an epic day of bike racing begins at 2pm on ITV4, ITV4 HD and ITV.com/tour.

Watch Gary Imlach's preview of the crucial Stage 19

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