5 things about the Tour de France Stage 13

CHAMROUSSE, France (AP) Scorching hot temperatures continued to fry riders on the Tour de France, with another sweltering day in the saddle for race leader Vincenzo Nibali as he extended his lead during Stage 13. Others were not so fortunate, such as Australia's Richie Porte, who dropped out of overall contention more than 11 minutes back and left his once mighty Team Sky looking for a new purpose at the Tour.

Here are five things to know about the Tour on Friday:

MOMENT OF SILENCE: The Tour de France briefly came to a halt Friday as riders and race followers held a moment of silence in honor of the 298 people on the Malaysian Airlines jetliner shot down over Ukraine on Thursday.

Before the start of the day's stage in Saint-Etienne the 177 riders still in contention stood silently over their bikes and the normally boistrous crowd of fans and onlookers joined them in a minute of quiet reflection.

The plane was brought down by what authorities say was a surface-to-air missile fired from a rebel-held area of eastern Ukraine.

Because the plane took off from Amsterdam, most of those killed were Dutch headed for Kuala Lumpur. Dutch squads Belkin and Giant Shimano wore black armbands over their cycling jerseys in an additional mark of respect for those killed in the attack.

BARDET IN WHITE: 23-year-old Frenchman Romain Bardet and his rival for the White Jersey, fellow Frenchman Thibaut Pinot, 24, continued their fight in the best young rider race, with each finishing the stage with reason to be happy.

Pinot narrowed his gap with Bardet, crossing the line half-a-minute ahead of his rival.

Bardet meanwhile kept the distinctive white jersey for top rider under 25 for a fourth consecutive day. The young AG2R team climber, riding his second Tour, has kept a low-profile but that would change overnight if he manages to keep his current podium spot all the way to Paris. The last time a Frenchman stood on the Tour's final podium was 17 years ago, when Richard Virenque finished 2nd in the 1997 Tour.

Bardet finished Friday's stage in seventh place, crossing the line 1 minute 23 seconds alongside 2012 White Jersey winner, American Tejay van Garderen.

Bardet, who finished 15th in his first Tour last year, said he's suffered in the scorching heat Friday in the Alps. ''It was suffocating, I felt like I was in a furnace,'' Bardet said.

PLAN C FOR SKY: Team Sky boss Dave Brailsford says the British squad will keep up its fighting spirit, even after Richie Porte's disappointing drop off the podium Friday.

Brailsford took a barrage of criticism for coming to the Tour without 2012 champion Bradley Wiggins. He now sees himself forced to look for a plan C, after original leader Chris Froome crashed out in Stage 5 and Plan B rider Porte plunged to 16th place from 2nd overall on the torrid ascent to the Chamrousse ski station.

Asked after the race how to explain Porte's collapse, Brailsford said ''I don't know is the honest answer. That wasn't the Richie that we've seen for the first part of the race.''

The Welshman promised that even decapitated of a second leader, Team Sky is ''not going to just roll over.''

''We recalibrated to our Plan B as it were, and now we've got to recalibrate again,'' Brailsford said outside the team's bus, while Porte and teammate Geraint Thomas cooled down nearby.

Porte shrugged off the disappointment and promised to soldier on.

''It happened to me so it can happen to the other guys too, so we just have to keep on pushing,'' Porte said.

ABANDONS: Three riders dropped out of the race during Friday's stage: Garmin Sharp's Janier Acevedo, Cofidis' Daniel Navarro, and Frenchman Arthur Vichot of Team FDJ.fr. Acevedo had been vying for the Red Lantern near the bottom of the Tour's overall classification, while Navarro was his team's best-placed rider at 37th overall. The 25-year-old Vichot was riding his fourth Tour, and had never previously abandoned the race.

In a message posted to his Twitter account, Vichot said he was ''gutted'' by the decision to abandon but that ''I ran out of strength.''

''That's high-level sports: there's no place for the weak and when you're sick, you're weak, so you're out,'' Vichot said.

Vichot had been one of the key lieutenants for FDJ.fr's top rider Thibaut Pinot. Team boss Marc Madiot said the loss of Vichot in the upcoming mountain stages will be a hindrance to Pinot's aim of taking the White Jersey or even making the Tour's final podium in Paris.

''It's always harmful to the team when someone abandons, it's better to be 9 than 8,'' Madiot said.

THE OTHER BADGER: Wisconsin native Matthew Busche worked hard all day for team leader Frank Schleck until the final punishing climb up to Chamrousse ski station. At that point, his work done, Busche peeled off and finished the climb in a small group almost 22 minutes behind stage winner Vincenzo Nibali. The 29-year-old riding his first Tour messaged on his Twitter account after the race ''Wow that was a doozy of a day.'' 5-time Tour champion Bernard Hinault, whose nickname is the Badger, would certainly agree.