Tom Dumoulin showed his time-trial prowess to win a sombre stage 13 of the Tour de France and Chris Froome avoided further drama to extend his overall lead to a minute and 47 seconds after finishing second on Friday.

Giant - Alpecin rider Dumoulin was full of confidence after a victory on stage nine and the Dutchman came out on top again in the 37.5 kilometre route from Bourg-Saint-Andeol to La Caverne du Pont-d'Arc.

Dumoulin clocked 50 minutes and 15 seconds in the first time trial of the Tour to claim an emphatic win, sending a message to his rivals ahead of the Olympic Games in Rio next month.

Team Sky's Froome took a big stride towards retaining his title by claiming second place after crossing the line 63 seconds slower than Dumoulin and Bauke Mollema moved into second place in the GC courtesy of a sixth-placed finish.

Froome was running up the Mont Ventoux in a chaotic conclusion to stage 12 on Thursday after Richie Porte crashed into a motorbike and the race leader ploughed into the Australian.

The Brit faced an anxious wait to discover whether he would relinquish the yellow jersey to Adam Yates before race organisers adjusted his time, and a day later he stretched his lead by a minute to stay on course to win the famous Grand Tour race for a third time.

Mollema (Trek – Segafredo) moved into second spot after Yates, now two minutes and 45 seconds adrift of Froome, could only clock the 18th-quickest time, while Nairo Quintana also lost ground and is now a further 14 seconds off the pace. 

A minute's silence preceded the stage and there was increased security on a sombre day following Thursday's suspected terrorist attack in Nice which left 84 people dead.

The race's publicity caravan remained silent Friday, along with start area and finish-line operations as a mark of respect.