ARGELÈS-GAZOST, France — Alexander Vinokourov, the manager of Vincenzo Nibali’s Astana team, said Nibali used Thursday’s final mountain stage of the Tour de France to show that he was the “padrone,” or boss, of the cycling world.

Nibali did more than that. Only illness, accident or profound bad luck are likely to prevent him from winning the 101st Tour de France on Sunday. No serious challenge to Nibali’s hold on the yellow jersey emerged as the mountain stages came to a close with a difficult, hot stage in the Pyrenees.

It was the Italian’s fourth stage win of this year’s Tour, three of them in the mountains. The last rider to win four non-time-trial stages in a single Tour was the Belgian Eddy Merckx. And that happened 40 years ago.

All of Nibali’s remaining challengers are too far behind to overtake him Saturday during the Tour’s only time trial, an individual race against the stopwatch. The other two remaining stages are flat, similarly eliminating the prospect of an upset.

Nibali, 29, was careful not to overtly declare himself the overall winner while nevertheless acknowledging that was the case.

“I’m very happy with this stage win, and certainly I’ve accumulated a healthy advantage, so I can remain calm for the next stages and Saturday’s time trial,” he said.

To drive home his domination, Nibali joined American Chris Horner, of Bend, in an attack on the final climb of the Tour, the road up to the Hautacam ski area near Argelès-Gazost. Nibali sat on the rear wheel of the bike of Horner, who won the Vuelta a España last year at the advanced age of 41.

Nibali said later that he was concerned that Mikel Nieve, a Spanish rider with Team Sky, who was up the road as the lone survivor of a prolonged breakaway, might have gained too much time. But given that Nieve had started the morning more than 36 minutes behind Nibali, Vinokourov’s analysis of Nibali had a truer ring to it.

After looking backward at the modest gap they had gained from the key group of riders, Nibali swiftly rode past Horner.

The climb to the spartan resort, often featured in the race, is rated off the scale by the Tour organization for difficulty, as was the day’s other major ascent, the Col du Tourmalet.

Not long after leaving Horner behind, Nibali zipped past Nieve without as much as a glance. Nieve was trying to salvage some kind of a result for Team Sky, which had a disastrous Tour de France after winning it the two previous years.

There was only one point on the final climb when Nibali did not seem to be in control. His elbow bumped a young woman who was using her smartphone. Nibali emerged unscathed, but the woman’s phone crashed to the ground.

Down the road, Alejandro Valverde, the Spanish leader of Movistar, was left behind as several riders, including the American Tejay van Garderen, attacked. They could gain only leftovers: either podium places or points in the mountain climbing competition.

Thibaut Pinot did not cross the line until 1 minute 10 seconds after Nibali. Pinot, of FDJ.com, is one of a contingent of French riders who have enjoyed an unusually successful Tour. His result put him in second place overall, 7:10 behind Nibali.

Rafal Majka, a Polish climber who was a last-minute selection of the Tinkoff-Saxo team, rolled in third. That left him with enough climber points to take the best climber’s spot away from Nibali.

Majka made no attempt to disguise his delight about becoming the king of the mountains, which comes with a polka dot jersey.

“My first Tour I have the jersey and two stage wins,” he said. “I’m very happy that I have my jersey.”

The early coronation of Nibali, or anyone else, was not the Tour organizers’ plan for this year. They left the time trial for the second-to-last day in the hopes of a last-minute result. (Sunday’s stage to Paris is largely ceremonial except for the sprinters.)

Before the race began, it seemed likely that a time-trial showdown would involve Alberto Contador and Chris Froome, the defending champion. But both abandoned the race earlier because of crash-related injuries.

Igor Tinkov, the owner of Contador’s Tinkoff-Saxo team, had suggested that Nibali, who has also won the grand tours of Italy and Spain, was winning by default. But several strong performances at the Tour by Nibali, particularly Thursday, meant that Tinkov held a minority opinion.

Nibali rejected the idea that he was emulating the style of the disgraced Lance Armstrong by imposing himself as the boss no rider dare cross.

“I’m very different than Lance,” said Nibali, whose news conference manner is certainly far less combative than Armstrong’s. “I haven’t done one huge performance. I got 30 seconds here, 40 seconds there.”

But with three days left in the Tour, those 30 seconds here and 40 seconds there have added up to a seemingly insurmountable lead.