6 Chicken breasts -- boneless
2 Cups Pineapple juice
2 Tablespoons Worcestershire Sauce
1/4 Cup Soy Sauce
2 Tablespoons Sugar

In a bowl combine all ingredients except for chicken. Stir.
Using a fork, poke about 5-8 sets of holes in each chicken breast.
Put chicken in marinade, making sure it is covered in the mixture.
Add more pineapple juice if necessary. Cover and refrigerate for 24-36 hours.
Grill.