French rider Paul Magnier wins Tour of Britain's opening stage
Riding for Soudal-QuickStep, Magnier produced a scintillating sprint to beat Israel-Premier Tech's Vernon, who finished one place ahead of fellow Briton Bob Donaldson.
Tom Pidcock, who claimed Olympic gold in the mountain bike cross-country race in Paris last month, finished fourth for Ineos Grenadiers.
Ineos tried to control the peloton in the final 10 kilometres, but Remco Evenepoel and Julian Alaphilippe took over at the front for QuickStep.
That paved the way for Magnier to build on the momentum of his second place finish in the recent Bretagne Classic-Ouest-France.
The 20-year-old Magnier's sixth stage win of the year earned him the leader's jersey.
"It's incredible, we did a really amazing team performance," Magnier said.
"Remco and Julian tried to go on the climb but it was really hard to get away, so then they worked for me for the sprint. They did it very well.
"I was in perfect position and I'm really happy to take the victory for the team."
The second stage on Wednesday will take place over 152.1 kilometres from Darlington to Redcar.
Stage one
1. Paul Magnier (FRA/SOQ) 4hr 11min 45sec, 2. Ethan Vernon (GBR/IPT) same time, 3. Robert Donaldson (GBR/TRI) s.t., 4. Tom Pidcock (GBR/IGD) s.t., 5. Casper van Uden (NED/DFP) s.t.
