After various attacks from the start of the race, a large breakaway group eventually established itself, achieving a lead of two minutes. From the breakaway group, Peter Sagan won the intermediate sprint at Bagnères-de-Luchon. Lilian Calmejane attacked the lead group with 70 km (43 mi) remaining in the stage, on the climb of the category 1 Col de Peyresourde to 1,569 m (5,148 ft), but was caught by Tim Wellens at the summit. Simon Clarke then went ahead, gaining a 40-second advantage on the descent. Matteo Trentin attacked from the breakaway group, at the beginning of the climb of the category 1 La Hourquette d'Ancizan to 1,564 m (5,131 ft), quickly catching Clarke, but with a five-man group only 15 seconds behind. Simon Yates and Gregor Mühlberger led the race over the summit, with Pello Bilbao a short distance behind. The lead group of three riders then stayed together to the finish, with Yates winning the sprint.
A lead group of seventeen riders established a three-minute lead over the peloton, before the category 1 Col du Soulor to 1,474 m (4,836 ft). Tim Wellens, Vincenzo Nibali and Élie Gesbert led up the climb, with Wellens leading over the summit. On the approach to the hors catégorieCol du Tourmalet, Romain Sicard was at the head of the race, 30 seconds in front of Gesbert and Lilian Calmejane. Gesbert caught and dropped Sicard with 13 km (8.1 mi) to climb, with Gesbert himself being caught by the lead group of general classification contenders at 10 km (6.2 mi) before the finish. With 1 km (0.62 mi) remaining, Geraint Thomas got detached from the lead group containing Alaphilippe, Buchmann, Pinot, Bernal, Landa and Kruijswijk. Thibaut Pinot attacked in the final 250 m (270 yd) and held his lead to the finish, at an altitude of 2,115 m (6,939 ft), for the Souvenir Jacques Goddet.
A lead group of 28 riders established itself by the Col de Montségur. The lead group was reduced to 16 riders on the climb of the Port de Lers. Simon Geschke attacked on the climb of the Mur de Péguère, with Simon Yates soon following. Yates caught Geschke at the summit, both 20 seconds ahead of the lead group. With 9 km (5.6 mi) to race, Yates attacked, holding a lead to the finish.
The stage occurred during the July 2019 European heat wave, with the temperature around 40 °C (104 °F) in the afternoon. A five-man breakaway group established itself early in the race, gaining a lead of around two minutes. With 130 km (81 mi) to race, Geraint Thomas crashed but was able to recover, later claiming that his bike's gears had jammed. Jakob Fuglsang crashed with 28 km (17 mi) to the finish, but was forced to abandon the race. The breakaway group was caught with 2.5 km (1.6 mi) to race, with the stage culminating in a bunch sprint.
A large breakaway group of 33 riders quickly became established. As there were no general classification contenders in the breakaway group, the peloton decided to conserve energy, instead of pursuing the group. The breakaway group's lead stretched out to 15 minutes, with 40 km (25 mi) still to race. Towards the end of the final climb, Matteo Trentin attacked from the breakaway group and held on to take the stage.Luke Rowe and Tony Martin were both disqualified from the Tour, following an altercation near the front of the peloton, in the latter part of the stage.
A group of more than thirty riders went ahead after 50 km (31 mi) of racing, gaining a four-minute lead on the approach to the Col de Vars. Tim Wellens led the group over the first climb, with the lead now extended to seven minutes over the peloton. Greg Van Avermaet and Julien Bernard went ahead of the lead group on the approach to the Col d'Izoard. Bernard then led alone on the climb but was caught before the summit, with Damiano Caruso leading a small group over the top. An eleven-rider group reformed at the foot of the climb to the Col du Galibier, which had a five-minute advantage over the peloton. On the Galibier, Nairo Quintana attacked with 7.5 km (4.7 mi) still to climb, leading by over a minute and a half at the summit, which he held on the descent to the finish. Meanwhile, with 2 km (1.2 mi) still to climb of the Galibier, Egan Bernal attacked from within the yellow jersey group containing Alaphilippe and Thomas, allowing Bernal to recover half a minute on the other general classification contenders by the finish.
Bernal, Alaphilippe and Peter Sagan, at the start of the stage
Around 40 km (25 mi) into the stage, Thibaut Pinot, who had been sitting fifth overall in the general classification and was noticeably struggling to deal with the pain of a muscle tear in his left thigh from the previous day, abandoned the race in tears after being unable to continue to ride with the pain.
The Souvenir Henri Desgrange was given to Egan Bernal, who was the first rider to summit the Col de l'Iseran, the highest climb of this race. As the riders began the descent of the Col de l'Iseran, the stage was neutralised due to snow, hailstorms, and mudslides rendering the road unsafe near Val-d'Isère on the ascent to Tignes, with times for the general classification being taken at the summit of the Col de l'Iseran. As a result, Bernal, who had been in second place, moved ahead of Julian Alaphilippe, who was nearly two minutes behind Bernal at the summit, and took the lead in that classification. Due to the neutralisation, there was no official winner of the stage, and the usual stage finish time bonuses of 10, 6, and 4 seconds for the first three finishers respectively were also not awarded. However, the special time bonuses of 8, 5, and 2 seconds on offer at the summit of the Col de l'Iseran were still awarded to the first three riders respectively to reach the summit.
Time gaps at the summit of the Col de l'Iseran[n 1]
The weather that caused the neutralisation of the previous stage also affected the route of this stage, with mudslides that rendered the descent off the Cormet de Roselend unusable. As a consequence, the stage was modified to avoid this part of the route, and shortened to 59 km (37 mi), keeping only the final 33 km (21 mi) climb to Val Thorens. All sporting points and time bonuses from the diverted route were withdrawn, leaving only those given on top of Val Thorens.
As the race travelled through the valley from Albertville to Moûtiers, a group of more than twenty riders established a two and a half minute lead over the peloton. On beginning the climb to Val Thorens, the lead group was reduced to four riders, with a further two riders then joining. With 12 km (7.5 mi) until the finish, Vincenzo Nibali attacked from the lead group. Nibali then held a lead to the finish line.
With 50 km (31 mi) still to race, after the peloton had completed a lap of the usual Champs-Élysées circuit, a four-man group comprising Jan Tratnik, Nils Politt, Omar Fraile and Tom Scully achieved a lead of over twenty seconds on the peloton. The group of four's advantage held until they were caught with 10 km (6.2 mi) to the finish. The peloton then headed the race into the finish. Edvald Boasson Hagen opened the sprint in the final 500 m (550 yd), before being passed by Maximiliano Richeze and Niccolò Bonifazio. Dylan Groenewegen and Caleb Ewan then took opposite sides of the road, to pass the other riders.
^These are not to be taken as actual stage results. Rather, they are the times of the first riders to reach the summit of the Col de l'Iseran, which is where the times were taken for this stage to determine the general classification.