Pascal Ackermann of Germany finished third, eight seconds behind his breakaway companions. Viviani's Italian teammates worked hard throughout the day and caused the split that left a group of 13 riders at the front before the leading trio moved away from the pack with two laps to go.
"I think we did a completely different tactic from what we were thinking this morning," Viviani said. "This morning we were thinking about the sprint, but then we wanted to make the race hard." With Viviani the best sprinter in the group, Lampaert attacked with 3.5 kilometers left to leave Ackermann and Viviani in his wake. Viviani waited patiently on Ackermann's wheel then surged ahead to close the gap with Lampaert, his Deceuninck-Quick Step teammate on the World Tour.
Lampaert launched the final sprint but quickly stopped his effort when Viviani passed him with ease. Less than a week after Belgian rider Bjorg Lambrecht died following a crash during the Tour of Poland, Viviani pointed a finger to the sky as he celebrated his win, then crossed himself.
"It's one of my best wins," said Viviani, who won the Prudential RideLondon-Surrey Classic last weekend and won a Tour de France stage last month. "It was totally different from a bunch sprint. After a Grand Tour, I always have a lot of resistance and big legs."
Alexander Kristoff won the main peloton sprint to finish fourth.
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