Heat oven to 375 degrees. Rinse and drain rice. Combine sausage and onion in skillet. Cook until brown. Drain. Combine soup, water, salt, and sage in a casserold dish. Microwave for one minute. Stir and add rice. Microwave for 15 minutes stirring halfway through. Add sausage mixture. Cover and bake at 375 degrees for 45 minutes.