Dalkala held on from Hughie Morrison's Shirocco Star in the Qatar Prix de Royallieu at Longchamp on Saturday.
Shirocco Star was second in the Epsom Oaks and the Irish Oaks earlier this season and was sent off a 5-2 favourite to claim her first success of the campaign.
However, Dalkala (3-1) was given a canny front-running ride by Christophe-Patrice Lemaire, who kept something up his sleeve for the finish.
Shirocco Star raced just off the pace under Darryll Holland and looked poised to go on and win when she was pulled out for her challenge.
However, although she tried hard to overhaul the leader, Dalkala kept on bravely and maintained a narrow lead all the way to the line, with La Conquerante finishing third.
