Richard Carapaz secured a commanding victory on stage 18 of the Tour de France on Thursday, as speculation mounted over the health of race leader Tadej Pogacar ahead of the crucial mountain stage. The Ecuadorian rider, a former Olympic champion, broke clear from a large breakaway group to win the 179-kilometre stage from Gap to Orcières-Merlette, finishing alone atop the final climb.

Carapaz, who rides for EF Education-EasyPost, attacked on the lower slopes of the category-one ascent to the finish line and held off a chasing group to take his second career Tour de France stage win. The victory was a significant moment for the 33-year-old, who has been a consistent presence in the mountains throughout this year's race but had not yet claimed a stage.

Behind him, the battle for the general classification took an unexpected turn as Pogacar, the defending champion and overall leader, appeared to struggle in the final kilometres. The UAE Team Emirates rider lost several seconds to his main rivals, including Jonas Vingegaard and Remco Evenepoel, raising questions about his condition with only two mountain stages remaining.

Reports from within the peloton suggested that Pogacar may be suffering from a stomach illness, a rumour fuelled by his choice of clothing during the stage. The Slovenian was seen wearing a different style of shorts than usual, which cycling insiders interpreted as a possible sign of discomfort or digestive issues. Neither Pogacar nor his team have confirmed any health problems, but the speculation has added an extra layer of tension to the race.

Stage 18 was the first of three consecutive days in the Alps, and the outcome has reshaped the dynamics of the general classification. Pogacar still holds the yellow jersey, but his lead over Vingegaard has been reduced to just over a minute, with Evenepoel lurking a further 30 seconds back. The stage on Friday, which includes the legendary Col du Galibier and a summit finish on the Col de la Loze, is expected to be decisive.

Carapaz, meanwhile, was delighted with his performance. Speaking after the stage, he described the win as a reward for his team's hard work throughout the race. He said he had targeted this stage from the start of the Tour and was pleased to execute the plan perfectly. The victory also moved him up several places in the overall standings, though he remains more than 10 minutes behind Pogacar.

The Tour de France has been marked by intense competition this year, with several top contenders trading blows in the mountains. Pogacar's dominance earlier in the race had seemed unassailable, but the emergence of health concerns has opened the door for his rivals. Vingegaard, the Danish rider who won the Tour in 2023, has looked increasingly strong in the high mountains, while Evenepoel, the world champion, has shown remarkable consistency in his first Tour appearance.

For Carapaz, the stage win is a highlight in a season that has also seen him finish on the podium at the Giro d'Italia. The Ecuadorian is known for his aggressive racing style and his ability to read races well, qualities that were on full display on Thursday. His victory was also a boost for EF Education-EasyPost, a team that has prioritised stage wins over the general classification this year.

As the race heads into its final weekend, the focus will be on Pogacar's health and whether he can hold off his challengers. The stage on Friday is widely regarded as the hardest of the Tour, with more than 5,000 metres of vertical climbing. If Pogacar is indeed unwell, the yellow jersey could change hands before the race reaches Paris on Sunday.

The Tour de France continues on Friday with stage 19, a 172-kilometre route from Embrun to Val Thorens that includes the Col du Galibier and the Col de la Loze. The stage is expected to be a brutal test for all riders, with the overall classification likely to be decided on its slopes.