The 157.7 km Stage 3 from La Sentinelle to Wallers Arenberg was the cobbled centrepiece of the race, running over the famous Paris-Roubaix sectors. Rasmus Tiller (Uno-X) got clear on the pavé and held on to take a solo victory by four seconds. Behind him, race leader Laurence Pithie showed his classics pedigree on the same cobbles, leading the chase home four seconds back to take second ahead of Jason Tesson (TotalEnergies). The selective finish thinned the GC group and left Pithie firmly in pink with the cushion he would defend to the end.

After the cobbles, Pithie led the GC by two seconds from stage winner Tiller, with Joppe Heremans (Van Rysel-Roubaix) and Liam Slock (Lotto-Intermarché) at +16s. The pure sprinters who had sat near the top earlier — Coquard among them — dropped down the order on the selective parcours, reshaping the overall into a battle between Pithie and a small group of all-rounders.