The sprint only became inevitable in the final three kilometres. A five-man breakaway had spent most of the day ahead before late reinforcements prolonged its resistance, but the final attackers were finally caught with around 3km remaining.
Lonardi delivers after Polti commit to the sprint
The peloton had spent much of the stage controlling Victor Vercouillie, Eirik Vang Aas, Henrik Teslo Fjellheim, Ludvik Holstad and Morthen Wang Baksaas, who formed the early escape and were allowed an advantage of around three minutes before the sprint teams began steadily reducing the gap.
NSN, Uno-X and Polti all contributed during the first half of the race with Vernon, Blikra and Lonardi among the leading sprint options, while Team Jayco AlUla later increased the pace through Christopher Juul-Jensen in support of Anders Foldager.
The breakaway battle also decided the first mountains jersey of the race. Baksaas won the opening KOM at Kåringen before Vang Aas took maximum points at Storvatnet, leaving the pair level heading towards the final categorised climb of Storeidet. Baksaas then edged a tight sprint at the summit to secure the jersey.
Lucky Sport Cycling Team tried to breathe new life into the move on Storeidet, with Finnish champion Axel Källberg and Teodor De Luca bridging across. That briefly increased Lucky Sport's presence at the front to three riders and helped the break maintain a small advantage deep into the finale.
Baksaas and Fjellheim eventually dropped back, but the remaining escapees still held around 20 seconds with 7km to go. De Luca then won the bonus sprint at the first passage of the finish line ahead of Vercouillie and Holstad, collecting six seconds before the race entered the final circuit around Myre.
Lotto Intermarché and Modern Adventure Pro Cycling both appeared prominently as the gap fell, while TotalEnergies took control for Tesson approaching the final kilometres. The break's cohesion finally disappeared and the last attackers were brought back at around 3km to go.
Polti then timed their move well. Three riders hit the front with roughly 2.2km remaining as the sprint trains fought for position, while NSN's organisation began to unravel behind. Vernon remained in the bunch but his lead-out became separated from him at a crucial moment, removing one of the strongest pre-stage favourites from prime position.
Tesson opened the sprint first, but Lonardi had the speed to come past and claim the opening stage of the race, rewarding Polti's commitment after a day in which they had helped control the break from the early kilometres.