Dutch cyclist Mathieu van der Poel won the prestigious Milan-San Remo 62 years after his grandfather with a late solo attack.
The 28-year-old broke away on the Poggio di San Remo summit with little more than five kilometres remaining.
Italy's Filippo Ganna was second, 15 seconds back, pipping third-place Wout van Aert and Tadej Pogacar to the line.
Van der Poel's maternal grandfather, French cyclist Raymond Poulidor, won the one-day Monument race in 1961.
"I cannot imagine a better scenario than this one," said the Alpecin-Deceuninck rider, who becomes the first Dutchman to win Milan San-Remo in almost 40 years.
"This is one of the races I really wanted to win. The way I won it today, it's beyond expectation. I'm really happy with this one."
Hennie Kuiper was the last rider from the Netherlands to win the race in 1985.
The 294km Milan-San Remo is one of five prestigious 'Monument' one-day races in cycling along with the Tour of Flanders, Paris-Roubaix, Liege-Bastogne-Liege and Giro di Lombardia.
Van der Poel has twice won the Tour of Flanders, in 2020 and 2022.
Britain's Tom Pidcock - who won the Strade Bianche classic last month - missed the race after suffering a concussion in Sunday's final stage of the Tirreno-Adriatico.
Mark Cavendish was the last British rider to win Milan-San Remo, for Colombia-HTC in 2009.
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