Ewan coasted off the wheel of Roger Kluge to take line honours ahead of Peter Sagan (Bora-hansgrohe) and Alex Edmondson (Mitchelton-Scott) in what was his first formal hit-out with new team Lotto Soudal.
Eli Viviani (Deceuninck-Quick-Step) and Phil Bauhaus (Bahrain-Merida) were among those that crashed in the closing laps and could not as result contest the reduced bunch kick.
“It was a bit unfortunate that there was the crash in the end," Ewan said. "Because when you sprint you want all the sprinters to be there.
"It’s hard to tell the indication against the other sprinters now because some of them went down but my feelings were good, the team rode great and had me in the position I needed to be in.
“It was a perfect start.”
Ewan effectively replaces veteran Andre Greipel (Arkea Samsic) as the marquee sprinter at Lotto Soudal this year and brought Kluge across with him from Mitchelton-Scott.
“You saw today he’s really one of the best at what he does. I’m honoured that he’d come with me. It’s good to have someone who is familiar with the way I sprint, and he knows what I like so it makes that transition into a new team a little bit easier,” the 24-year-old said.
Italian national champion Viviani appeared fine as he checked himself past the finish line where teammate Michael Morkov sported ripped kit and counted a couple of leg abrasions. The pair were involved in a crash in the final lap that reduced the bunch to the line.
Bauhaus was okay after he was caught up in a separate stack with two laps to go.
“I have the feeling a rider came and I couldn’t do anything and then crashed. I just lost a bit of skin,” he said.
Ewan is treating the collective misfortunes as temporary, preparing for a response when the WorldTour season officially kicks off from Tuesday.
“It’s such a strong sprint field here. I think it’s probably the best one they’ve had in a long time. It’s definitely not going to be easy to win sprints when the tour starts,” he said.