Fox, 25, had good control of the distance from the first round and successfully outboxed Venezuela's two-time Olympian. In the second round, Maestre hit the floor after a precise left hand.
After twelve rounds, the American landed more punches and seemed to deserve the victory, but the judges gave the victory to the Venezuelan - 114-113, 115-112 and 117-110. For Maestre, this was the first professional performance in the United States.