Bayakoa defeated arch-rival Gorgeous by three lengths to win the $268,625 Grade I Spinster Stakes at Keeneland Race Course on Saturday.
Bayakoa covered the 1 1/8-miles over a fast track in a stakes-record 1:47 as Keeneland opened its fall meet.
Jockey Laffit Pincay never whipped Bayakoa, who eased into the lead with about a half-mile to run.
Bayakoa, the 4-5 favorite, paid $3.60.
The victory was Bayakoa's sixth in nine starts and boosted her lifetime earnings to $2,296,273.