MIX barbecue sauce, orange peel and juice. Reserve 1/2 cup of the barbecue sauce mixture. Pour remaining barbecue sauce mixture into shallow baking dish. Add chicken; turn to evenly coat both sides of each chicken breast. Cover.
REFRIGERATE 30 min. to marinate. Drain; discard marinade.
PREHEAT greased barbecue to medium heat. Grill chicken 12 to 15 min. or until cooked through (170°F), turning and brushing occasionally with the reserved 1/2 cup barbecue sauce mixture after 8 min.
