Merlier wins sprint battle in Paris-Nice opener
Tadej Pogacar collected a bonus on the last climb to take a six-second advantage over the reigning Tour de France champion Jonas Vingegaard which could be useful in an eight-day race often decided by just a few seconds.
At the end of a winding and hilly 169.4 kilometre circuit in the Chevreuse Valley, west of Paris, Merlier, of Soudal-Quick Step, pulled away in the final metres.
Four other sprinters crossed the line shoulder-to-shoulder a bike length behind. Irishman Sam Bennett of Bora claimed second and Dane Mads Pedersen third.
The bonuses mean Merlier leads overall with Bennett and Pogacar four seconds behind.
"I can't say how great it was," said Merlier.
He joined Soudal, a team with a tradition of sprinters, this season and opened his campaign with a Tour of Oman stage victory followed by three at the UAE Tour.
"I'm having a fantastic start to the season, it's great for me and the team," said the 30-year-old Belgian, who will wear the leader's yellow jersey on Monday.
Soudal, a team that specialises in sprints, took control in the run in.
The two Tour de France winners, Slovenian Pogacar and Dane Vingegaard, were both active in the final 20 kilometres.
Pogacar attacked on the last two hills and collected bonus seconds when he was first over the last one.
Vingegaard gave chase but crested fourth to miss the bonus. The momentum carried the two men clear as part of a breakaway trio with six kilometres left but after a chat, the two heavyweights sat up and allowed the sprinters to battle for victory.
"We went after the bonus sprint," Pogacar told Eurosport after the finish.
"We got the gap but we were just two guys working, it was enough and a head wind also. So it was obvious it was going to be a sprint. I saw that. Waited in the bunch and safely across the finish line."
The double Tour de France champion said he did not feel strong at the start "but every hour in, I felt better."
There were several crashes in the jittery bunch during the day.
"Was hard day definitely," said Merlier. "A lot of stress in the peloton."