Marlen Reusser took the overall lead in the Tour de France Femmes on Tuesday, after a carefully executed plan to win the 21-kilometer time trial between Gevrey-Chambertin and Dijon.
The Swiss rider revealed she had been targeting the stage win and the yellow jersey since last year.
"It worked, and I'm really happy. This was my objective here. We called it our 'mustard plan'," she said, referring to the mustard produced in Dijon where the time trial ended.
Marlen Reusser Takes Yellow Jersey In Dijon
Pre-race favorite and 2023 champion Demi Vollering was just 18 seconds slower in third on the day, and trails Reusser by only 14 seconds overall.
Defending champion Pauline Ferrand-Prévot is now 2 minutes 13 seconds off the pace, while 2024 winner Kasia Niewiadoma is 1 minute 9 seconds down.
France's Ferrand-Prévot will still be considered an overall contender, though, after beating Vollering by more than three minutes in the penultimate stage last year en route to the title.
World time trial champion Reusser, a qualified doctor, was left lying on the floor and breathing heavily after the finish, while Vollering, the better climber, appeared to have measured her pace.
"It wasn't perfect, perfect, but it was good," said Reusser. "I started well, I did a good climb, but I had a little bit of a problem with my bike and the wind."
Demi Vollering And Pauline Ferrand-Prévot Stay In Contention
The peloton were subjected to clothing checks ahead of the time trial to ensure no chest form-altering clothing was being used for aerodynamic advantage.
UCI rules state riders may not use any objects to artificially change their "morphology," including cooling devices, padding or front body radio pockets.
Reusser will have to survive Friday's monster climb of Mont Ventoux if she is to take her first Tour de France Femmes title.
She may also come under pressure on Wednesday's fifth stage, which features eight hills and ends in the Beaujolais region.
The race concludes on the Promenade des Anglais in Riviera city Nice on Sunday.