It was a messy final few kilometres as a number of teams battled to control the sprint. Cofidis lead the peloton for their sprinter, Viviani, in the final 500 metres before Juan Sebastián Molano (UAE Team Emirates) hit the front to lead out Fernando Gaviria.
The Colombian tried to launch his sprint along the barriers, but his teammate moved right into him as he pulled off the front, frocing Gaviria into the barriers, with the Colombian fast man sliding along the barriers with his shoulder but somehow avoiding a crash.
Merlier jumped around the outside and then was able to extend his lead, in the end outlasting Nizzolo and Groenewegen, with a flying Viviani coming home late to pip Groenewegen for third.
“I'm really happy, really proud of taking a Grand Tour win,” said Merlier. “I knew there was a roundabout that was really important in the end. When I saw it I knew I was in a good position. When I came out I was thinking we need to go faster, faster, faster. I went from far out - 250 metres - but in the end, it was enough. This is a big victory.”
Merlier held up his fingers in the shape of the letter 'W' to remember fellow Belgian Wouter Weylandt, who died after a crash at the Giro d’Italia exactly ten years ago.
"I am just happy I could do this for him," said Merlier.
Filippo Ganna (Ineos Grenadiers) finished safely in the peloton to retain the race leader’s maglia rosa. He he even extended his lead in the overall standings after taking out the intermediate sprint with 26 kilometres to go, his advantage is now out to 13 seconds over fellow Italian Eduardo Affini (Jumbo-Visma).
“I sprinted (at the intermediate sprint) just for taking the seconds, not for the other jerseys but to take away time from the other leaders, and so to help Egan and Pavel in the GC in the next few days," said Ganna. "If we take the jersey or not for three seconds, it will be worth it.”
Remco Evenepoel (Deceuninck-QuickStep) showed he was ready to fight for every scrap of time out on the road, sprinting to second and picking up two bonus seconds.
Ganna was wary of the threat to his maglia rosa on Monday’s hilly stage in the Piemonte hinterlands, with aggressive racing expected over the final kilometres. For the moment, the Italian was enjoying the spotlight in his home race.
"It was super amazing today, there were a lot of people cheering for me, it was really special,” said Ganna. “We know tomorrow is hard and a perfect stage for [Peter] Sagan because there's a lot of up and down, really narrow roads. But we can try to have the jersey for another day.”
Filippo Tagliani (Androni Giocattoli-Sidermec), Umberto Marengo (Bardiani-CSF-Faizané) and Vincenzo Albanese (Eolo-Kometa) were the all-Italian early break of the day, the carrot for the peloton to chase as the sprinters prepared for a final dash to the finish in Novara.
After 40km of racing the gap reached its maximum of four minutes and 20 seconds but the sprint teams began to take over the pace-making from INEOS Grenadiers to keep them in check, with Lotto Soudal, Alpecin-Fenix and Jumbo-Visma doing the work to bring the lead back to hover around two minutes.
The only categorised climb of the day in Montechiaro d'Asti was the main prize for the breakaway in addition to the TV time, as it would decide who in the break would take the blue mountains jersey. The break nearly came to a standstill as they approached the line, with Albanese showcasing his uphill sprint to secure a trip to the podium for Eolo-Kometa.
Coming into the finale, the break was reabsorbed with 26 kilometres to go and then the final intermediate sprint saw a bit of disorginisation at the head of affairs, with Ganna and Evenepoel the most aware and nabbing the best bonus seconds, with Iljo Keisse (Deceuninck-QuickStep) in third.
Movistar, Deceuninck-QuickStep and INEOS kept near the front of the peloton to avoid any problems as the sprint trains began to organise near the front, before Bora-Hansgrohe moved up in mass with four kilometres to go and really put the pace on.
No one team could lead out the sprint. Daniel Oss tried to line out the sprinters in the final kilometre but the leadouts became mixed and in the end it was UAE Team Emirates and Alpecin-Fenix that had their chosen sprinter in the best spot in the finale.
Merlier timed his sprint well and surged clear in view of the finish, holding on to win and salute with his fingers forming a 'W' in tribute to the departed Wouter Weylandt.
Australian Caleb Ewan (Lotto Soudal) was well out of position coming into the final sprint and swung off with a few hundred metres still to ride, finishing tenth on the stage.
The Giro d'Italia continues on SBS with Stage 3, a hilly stage from Biella to Canale over 190 kilometres that offers opportunities for the climbing sprinters and attackers. Watch the race on SBS OnDemand from 2010 AEST, with the SBS VICELAND coverage starting at 2120.