The European champion, of Crew Bahrain Victorious, pipped Belgian Florian Vermeersch (Lotto Soudal) and Dutchman Mathieu van der Poel (Alpecin-Fenix), who had been second and third respectively.
Van der Poel, one of many pre-race favourites, got here up simply quick after doing a lot of the work in a small group chasing Italian Gianni Moscon, who gave the impression to be heading to victory earlier than a puncture and late crash ruined his possibilities.
Moscon (Ineos-Grenadiers) finally completed fourth, 44 seconds off the tempo, leaving his compatriot Colbrelli to grow to be the primary Italian to win right here since Andrea Taffi in 1999.
“Immediately is a legendary Roubaix with the rain and the climate at the beginning and an assault with 90km to go after Arenberg,” mentioned Colbrelli.
“I adopted solely Van der Poel within the finale and in the long run I had a brilliant dash. I used to be on the restrict within the finale. It was tremendous tough as a result of I had to concentrate for the crashes from the primary sectors after which there’s all the time the stress to be in place on the cobbles. This 12 months is my 12 months, I am very blissful.”
Van der Poel, who was additionally making his debut on the Paris-Roubaix within the first version since April 2019 after the Covid-19 pandemic prompted organizers to place off the occasion, matched his father Adrie’s podium end from 1986.
Numerous crashes marred the race with triple world champion Peter Sagan hitting the deck and Swiss Stefan Kueng happening 3 times.
Colbrelli spent a lot of the day tucked into Van der Poel’s slipstream, and when the ultimate dash on the Velodrome loomed, the Italian was the freshest man.
It lengthy appeared, nonetheless, that Moscon could be celebrating a solo win.
Moscon pulled away from a number one group within the cobbled sector of Auchy-lez-Orchies to Bersee 49km from the road because the solar pierced via the clouds and the roads began to dry.
Coming into the important thing cobbled sector of Mons-en-Pevele, Moscon led Vermeersch and fellow Belgian Tom Van Asbroeck by 35 seconds and Van der Poel, Canada’s Guillaume Boivin and Colbrelli by 1:10.
Powering his means via the thick mud, Moscon prolonged his benefit over the Van der Poel trio to 1:25 as Belgian Wout van Aert pale away.
With 38km remaining, Vermeersch and Van Asbroeck had been reined in by Van der Poel and firm and the newly shaped group organized the chase behind Moscon.
The Italian misplaced some 30 seconds with a flat rear tire that prompted a motorbike change 29km from the road with the chasing quintet lowering the hole to 45 seconds.
It fell to fifteen seconds after he crashed on a muddy patch, however the Italian stayed simply clear as Boivin crashed within the group of chasers within the cobbled sector of Camphin en Pevele.
He was, nonetheless, caught and dropped 16km from the end within the Carrefour de l’Arbre as Colbrelli, Van der Poel and Vermeersch went clear to contest the ultimate dash.