The Bora Hansgrohe rider finished over a length clear of many of the sports best sprinters to claim the 190 kilometres 3rd stage of Paris Nice.
Among those left in his wake were Grand Tour stage winners Alexander Kristoff, John Degenkolb, Marcel Kittel and André Greipel.
This was the 26 year olds first World Tour triumph – he is the first Irish rider to win a stage of Paris-Nice since Stephen Roche won the Col d'Eze time trial in 1989.
Fellow Carrick man Sean Kelly won the race a record 7 times.
Ireland's Dan Martin remains ninth on general classification, 23-seconds off leader Arnaud Demare.
