Sven Nys was world cyclocross champion and one of the discipline's defining riders through the 2000s, and his son grew up at the races. Thibau won the junior world cyclocross title at Dübendorf in 2020, the under-23 title at Hoogerheide in 2023 and the under-23 World Cup that same winter. The under-23 European road race title had come earlier, in 2021, when he was eighteen, and expectation in Belgium ran well ahead of him.
Trek took him onto the road squad while Baloise Trek Lions kept him through the winters, which left him racing almost year round. He won a stage of the Tour of Norway in 2023, then in 2024 took his first WorldTour win at the Tour de Romandie, the Tour de Hongrie overall and stages at the Tour de Suisse and the Tour de Pologne.
He opened 2025 by winning the GP Miguel Induráin on his first race day of the year, then rode the Ardennes classics for the first time, eighth at Flèche Wallonne and fifth at Liège-Bastogne-Liège. He went to the Tour de France in July for his first Grand Tour, arrived carrying illness, crashed on the first day and got nothing out of the race.
Wout van Aert and Mathieu van der Poel had made the road-and-cross double the template before him, and Nys came into elite racing measured against them. His first elite World Cup win came at Waterloo in the 2023-24 season. He took the European title at Pontevedra in 2024, his first Belgian elite title in January 2025, and finished third at the Liévin World Championships behind Van der Poel and Van Aert.
He wins on short steep finishes, from reduced groups and uphill sprints, and rides a closing kilometre with the handling of a cyclocross racer. The 2025-26 cross season opened with the Koppenbergcross on 1 November. He lost the European title to Toon Aerts at Middelkerke on 9 November, then won the Flandriencross at Hamme a week later.
He won the opening World Cup rounds at Tábor and Flamanville and beat Tibor Del Grosso at Dendermonde on 28 December. He was second to Van der Poel at Namur, Gavere and Benidorm, and second to him in the final World Cup standings. A second Belgian title came at Beringen in January 2026, and he was third again at the Hulst World Championships, behind Van der Poel and Del Grosso.









