Place chicken in self-sealing plastic bag along with half of teriyaki sauce. Seal; marinate at least 1-2 hours, turning once or twice. Remove chicken from bag. Discard marinade. Grill chicken breasts over medium heat about 6-8 minutes on each side or until done. Baste with remaining teriyaki sauce while cooking, 2 to 3 times.
Add sandwich rolls and pineapple slices to grill the last few minutes while cooking chicken, turning once to lightly brown both sides.
Top each bread slice with lettuce, tomato, chicken breast, and finally with pineapple (optional).