Hello and welcome to live coverage of stage 20 of the Tour de France - the all-important 22.5km individual time trial in Marseille, where the destiny of the yellow jersey will finally be decided...

Yates is 47 seconds down at the first check... meanwhile, Barguil is all smiles as he reaches the top of the climb, 46 seconds down on Kwiaktowski's effort.

Contador is sixth at the first check - 13 seconds down on Kwiatkowski's target time.

Chris Froome (Team Sky) is roughly 28 minutes away from winning a fourth Tour de France. He carries an advantage of 23 seconds over Bardet and 29 seconds over Uran - so he won't need to push too hard. But he will want to win a stage as well, so expect him to give it his all.

The crowds go crazy as Romain Bardet (Ag2R-La Mondiale) starts his effort... does he have what it takes to win the Tour in what is essentially Froome's back garden (when it comes to expertise).

Rigoberto Uran rolls down the ramp for Cannondale-Drapac. What a huge half an hour for the Colombian - this is his best ever shot at winning a Grand Tour...

Could Mikel Landa ride himself onto the podium and put himself in the shop window? There's talk that the Spaniard will leave Sky at the end of the season. He's down the ramp now, leaving just the top three to go...

Fabio Aru of Astana is back in blue and without his Italian national champion's jersey today. He wore yellow for a couple of days before cracking in the Massif Central and being hamstrung by apparent bronchitis in the Alps.

Ireland's Dan Martin is next up for Quick-Step Floors. He's 2:56 down on Chris Froome but we'll never know how much of a greater threat he may have been had Richie Porte not taken him out on the descent of the Mont du Chat in stage 9.

Simon Yates of Orica-Scott zips off - he's got to defend his white jersey from Meintjes today...

Louis Meintjes of UAE Team Emirates the next to roll down the ramp. Rumour has it he's heading back to Dimension Data next year...

Warren Barguil has gone full polka dot with the red bib shorts... while the climb will suit him, the Frenchman is not a great time triallist so don't expect great things from him.

Top ten time: Alberto Contador (Trek-Segafredo) rolls down the ramp - and this could well be the Spaniard's last chance to win a stage on the Tour de France.

Nairo Quintana - on course for his lowest finish in the Tour de France - rolls down the ramp. The Colombian has only ever finished on the podium in the Tour, but this year has slumped to 12th place after his failed attempt to win the 100th edition of the Giro d'Italia. This is his fourth consecutive Grand Tour and Quintana is wisely giving the Vuelta a wide berth next month.

French national champion Pierre Latour sets the 10th best time at the second check after the climb. And here comes Sylvain Chavanel, the French veteran of 17 Tours and former national time trial champion, who sets the sixth best time. Solid efforts from the two Frenchmen.

Roglic, after that bike change, could only post the 10th quickest time today - 49 seconds down on the leader, Bodnar.

NEWSFLASH: Warren Barguil, the polka dot jersey and winner of two mountain stages, has been voted the Super Combatif of the 2017 Tour de France. It was always going to be a toss up between him and the Belgian Thomas De Gendt, who managed to notch more than 1000km in breakaways. But it seems like Barguil's nationality got him over the line...

The current top ten...

Yes, Roglic was ninth quickest at the first check (25 seconds down) and ninth at the second check (38 seconds down) so it's not going to be his day.

Mechanical: Roglic has had to change his bike ahead of the climb so that may discount him from winning today. We're still waiting for confirmation of his time at the first check so we don't know whether he was on course of not.

This is how much Tony Martin put into that time trial... For now, he's third place after Polish duo Bodnar and Kwiatkowski.

Heartbreak for Michal Kwiatkowski! He crosses the line just over one second down on his Polish countryman, Maciej Bodnar, who stays in the lead.