In a sauce pan combine the water, sugar and sage, bring to a boil and cook for 2 minutes. Cool to room temperature (The syrup can be prepared in advance).

In a tall cup place the grapefruit segments and with a wooden spoon mash them together. Move it to a shaker, add ice and the rest of the ingredients (use a tablespoon of sage simple syrup). Shake and serve in a cocktail glass.