Place lamb in large glass baking dish. Rub with rosemary and garlic. Pour wine and oil over; turn to coat. Cover and refrigerate overnight. Prepare barbecue (medium heat). Remove lamb from marinade. Pour marinade into heavy small saucepan and bring to boil. Set marinade aside. Place lamb on grill. Cover and cook until thickest parts of lamb register 135°F on thermometer, turning frequently and basting with marinade, about 25 minutes. transfer to platter and let stand 10 minutes. Slice lamb on diagonal and serve.