Make Ginger-Sage Syrup: In a small saucepan, bring ginger, sage, sugar and water to a simmer. Gently simmer until sugar dissolves. Remove from heat and let cool to room temp; strain into jar or measuring cup.
Make cocktail: In a cocktail shaker filled with ice, shake rye, lemon juice, Ginger-Sage Syrup and maraschino liqueur until cold. Strain into a glass and top with a dash of bitters and fresh sage.