Pour 1/2 of pineapple mixture into a heavy-duty zip-top plastic bag; add fish. Seal bag and marinate in refrigerator 2 hours, turning bag occasionally. Set aside remaining pineapple mixture.
Coat a grill pan with cooking spray.
Brush with vegetable oil.
Place over medium- high heat until hot.
Remove fish from bag; discard marinade.
Place fish, skin side up, on grill pan; grill 5 minutes or until browned. Turn fish; reduce heat to medium. Grill 10 minutes or until fish flakes easily when tested with a fork.
Bring reserved pineapple juice mixture to a boil in a small saucepan over medium-high heat. Boil 10 minutes or until mixture is reduced to 1/4 cup.