Swiss rider Marlen Reusser won the fourth stage of the Tour de France Femmes on Tuesday, setting the fastest time in the individual time trial from Gevrey-Chambertin to Dijon and taking the yellow jersey in the process.

Reusser, who rides for Movistar, was quickest on the course through the Côte-d'Or, beating the rest of the field against the clock to secure the stage victory. Her winning ride also lifted her to the top of the general classification, making her the new leader of the race.

A time trial is a pure test of individual performance. Riders set off alone and are timed over the same course, which makes the result a direct measure of form and fitness. Unlike a normal road stage, there is no opportunity to hide in the pack or rely on teammates to chase down attacks. For the general classification contenders, the stage in the Côte-d'Or was one of the first major moments of this year's Tour, and the final gaps were significant.

The day belonged firmly to the Swiss rider, but it was a different story for Pauline Ferrand-Prévot. The Visma Lease a Bike rider was distanced by the other favourites in the fight for the general classification and conceded more than two minutes on the stage. «I'm glad this day is over», she said afterwards.

Ferrand-Prévot had been expected to play a prominent part in the race, but the time trial proved to be a costly day for her hopes. The time she lost leaves her facing a much harder path if she wants to move back into contention for the overall title over the coming days.

Reusser's success was complete in both ways that matter in a stage race. She took the stage win and, with it, the race lead. For Movistar, the result is an early sign that the team's plans are working, while Reusser will now have the responsibility of defending the yellow jersey when racing resumes.

The general classification picture has therefore changed after just four days. Reusser starts the next stage at the head of the standings, with the other main contenders looking to make up time and challenge her authority at the top of the race.

From now on, the Swiss rider will be closely watched by her rivals, who will look for chances to reduce her lead in the remaining stages. At the same time, Ferrand-Prévot will need to respond quickly if she is to avoid falling further behind in the battle for the overall classification.

Attention now turns to the next stages. The race remains wide open, and the time trial has already given the peloton a clear signal about the form of the current race leader and the difficulties facing some of her rivals.