Chris Froome was penalised 20 seconds for taking an illegal feed inside the final five kilometres on today's double ascent of the Alpe d'Huez, but still increased his overall lead in the 100th Tour de France.
As Christophe Riblon raced to victory ahead to become France's first stage winner this year, Froome showed his first signs of distress all Tour when he waved for help just after the 5km post.
Richie Porte dropped back to the team car to get an energy bar for the yellow jersey holder, but race commissaires docked the time from Froome.
Nevertheless, he still increased his lead over Alberto Contador to five minutes 11 seconds after finishing in seventh place, almost a minute ahead of the Spaniard on the road.
"That's one of those things that comes with the race," Froome said of the penalty. "I really felt that I needed those sugars at the end. If it comes with a 20-second penalty I have to accept that."
Porte was also docked 20 seconds for his role in the incident.
Froome has looked imperious on the climbs during this Tour, winning on the toughest mountain stages in Ax 3 Domaines and on Mont Ventoux.
But today he clearly struggled on the second of the two ascents.
Although he had kicked clear of Contador with around 11km to go, Nairo Quintana stayed with him and the Colombian eventually finished more than a minute clear, putting him third overall five minutes 32 seconds back.
Froome had finished seventh alongside Porte in sixth, and - regardless of any penalty - he will be happy to see his overall lead increased on such a dangerous stage.