Precooking food partially in the microwave, oven, or stove is a good way of reducing grilling time.  Just make sure that the food goes immediately on the preheated grill to complete cooking.

Cook food to a safe minimum internal temperature to destroy harmful bacteria.  Meat and poultry cooked on a grill often browns very fast on the outside.  Use a food thermometer to be sure the food has reached a safe minimum internal temperature.

Cook chicken to a minimum of 165°F, hamburgers to a minimum of 155°F, pork products, whole fish, fish fillets to a minimum of 145°F, and cook other potentially hazardous foods to a minimum of 135°F.

Never partially grill meat or poultry and finish cooking later.

When taking food off the grill, use a clean platter.  Don't put cooked food on the same platter that held raw meat or poultry.  Any harmful bacteria present in the raw meat juices could contaminate safely cooked food.

After cooking meat and poultry on the grill, keep it hot until served – at 135°F or warmer.

Keep cooked meats hot by setting them to the side of the grill rack, not directly over the coals where they could overcook.  At home, the cooked meat can be kept hot in an oven set at approximately 200°F, in a chafing dish or slow cooker, or on a warming tray.

Source:  USDA Food Safety and Inspection Service
             FDA 2005 Food Code