Skjelmose came through Danish club racing and was among the better juniors in Europe by 2018, second overall at the Course de la Paix Juniors behind Remco Evenepoel and third at Paris-Roubaix Juniors. That July a test returned methylhexanamine, traced back to a dietary supplement, and he served a ten-month suspension. He returned at Continental level, rode a stagiaire spell with Trek in 2020 and turned professional the following year.
The Tour de Luxembourg in 2022 gave him a first stage race overall, built on a win in the time trial stage. In 2023 he was second to Tadej Pogačar at La Flèche Wallonne, then won a mountain stage at the Tour de Suisse and held the overall by nine seconds from Juan Ayuso, with Evenepoel third. Gino Mäder died during that race and Skjelmose dedicated the win to him. The Danish road title and the Maryland Cycling Classic followed.
Through 2024 the week-long races brought podiums: fourth at Paris-Nice with a stage win, third at the Tour of the Basque Country, third at the Tour de Suisse. The Vuelta a España brought fifth overall and the young rider classification, his strongest Grand Tour ride. His Danish time trial title from that year took a year to settle, after Johan Price-Pejtersen set the fastest time and was disqualified, and Skjelmose objected to being handed the jersey.
He rides well against the clock, climbs with the leaders on long mountain days and finishes fast out of small groups on short steep hills. Those are the demands of the Ardennes and of the week-long stage races, which is where his wins have come.
At Amstel Gold Race in 2025 Pogačar went clear with 47 kilometres to go, Skjelmose and Evenepoel closed him down inside the final eight, and he came round both in the sprint. He extended to 2028 weeks later. A stomach infection cost him the Critérium du Dauphiné and the Tour de Suisse, and he abandoned the Tour de France on stage 14 after hitting road furniture out of Pau. He finished fourth in the world road race in Kigali.









