Light a grill or preheat a grill pan over medium-high heat. Peel the grapefruit and lime.

Squeeze the juice of half of the grapefruit and lime into a medium non-reactive bowl.

Stir in half each of the olive oil, cilantro and mint. Season with half of the salt. Add the chicken and toss to coat. (Option: Marinate 30 minutes or up to 4 hours)

Grill the chicken drumsticks over moderately high heat, turning them occasionally, until they are cooked through, 8 to 10 minutes.

Meanwhile, coarsely chop the remaining grapefruit and lime sections and transfer to a bowl. Add the red onion and the remaining olive oil, cilantro and mint. Season with salt.

Serve the chicken thighs with the citrus salsa.