Preheat oven to 400°F. In a large bowl mix grapefruit juice, oil, garlic powder, cumin, paprika, and red pepper until combined. Add chicken to bowl and turn to coat. Refrigerate until ready to bake.
For salsa fresca: In a medium bowl mix grapefruit segments, jicama, red onion, grapefruit juice, olive oil, cilantro, and jalapeño pepper until combined. Refrigerate until ready to serve.
Remove chicken from marinade. Place chicken in baking dish. Bake 25 to 30 minutes or until chicken is cooked through. Serve chicken with salsa fresca. Makes 5 servings. Recipe from Culinary.net.