The Jimmy Takter pupil followed mid-pack as elimination winner Good Will Hanover laid down fractions of :26.1, :54.3 for the half and 1:22.2 for three-quarters.
Into the final turn, a first-up Lindwood Beachgirl put pressure on the tempo-setter as Newborn Sassy followed second-over. Pure Country, the 2-1 favourite, found live third-over flow after being shuffled back to seventh.
Pure Country angled off cover at the head of the lane, and once the pacing miss was fed open racetrack, she marched past her foes to capture the rich final in a new lifetime mark of 1:49.3.
Darlinonthebeach finished second, one length behind the victress. L A Delight got up for third.
"There is nothing better than owning and breeding, and then ending up winning one of these races like this," said Diamond Creek Racing's Adam Bowden. "He [Brett Miller] was third-over coming off the final turn. She looked like she was full of pace and I was confident."
Pure Country notched her second victory of the season and 12th lifetime. With the win, the daughter of Somebeachsomewhere and Western Montana earns millionaire status, lifting her career earnings to $1,178,953 for owner/breeder Diamond Creek Racing.
Pure Country paid $6.10 to win.
Mark McKelvie