The former clubhouse at Federal Field was home to the Federalsburg Athletics of the Class D Eastern Shore League, a minor league affiliate of Connie Mack's Philadelphia Athletics. Fifteen players from the A's reached the Major Leagues: Robert "Ducky" Detweiler, Clarence "Buck" Etchison, Gene Hermanski, Sam Holbrook, Lew Krausse, Walter Masterson, Charlie Moss, Richard Mulligan, Barney Mussill, Ron Northey, Joe O' Rourke, Elmer "Pep" Rambert, Joe Rullo, Elmer Valo, Jack Wallaesa, and Charles "Spider" Wilhelm.