Brothers Eric and Albert Wirth of Douglaston, N.Y., teamed up to purchase their first Thoroughbred in the late 1960's, and have been breeding and racing horses, primarily in Maryland, ever since. One of their newest players, the promising 3-year-old Maryland-bred filly Spirited Game, conditioned by the brothers' longtime trainer Ron Cartwright, scored one for the home team when she won the Smart Halo Stakes on April 4 at Pimlico.