2/3 cup olive oil 1/2 cup plus 2 Tablespoon dry red wine 1/4 cup red wine vinegar 2 tablespoons balsamic vinegar 5 tablespoons fresh rosemary, diced 10 garlic cloves, pressed 5 lb. leg of lamb, butterflied, with bone removed salt and fresh cracked pepper to taste Mix all the ingredients, except the salt and pepper, in a big glass bowl and add the lamb. Turn several times with your hands to make sure that all the lamb is covered. Cover with plastic wrap and refrigerate for at least 24 hours, turning every now and then. Remove from the fridge about an hour before grilling in order to return lamb to room temperature. Remove lamb from marinade and sprinkle generously with salt and fresh cracked pepper. Grill the lamb on the center of the barbecue grill for about 17 minutes over a medium heat for medium rare, 23 minutes for medium. Don\'t worry about the flare−ups as it will give the lamb a delicious, crispy skin. Turn the meat only once and cook for another 17 to 23 minutes, depending on desired doneness. Remove lamb from grill and tent with tinfoil for 20 minutes to allow juices to settle. Carve.