Place scallops and tomatoes alternately on 4 (12-inch) skewers; brush with 1 tablespoon teriyaki sauce.
Coat grill rack with cooking spray; place on grill over medium-hot coals (350 to 400).
Place kabobs on rack, and grill, uncovered, 5 minutes. Turn kabobs, and brush with remaining teriyaki sauce; grill 10 additional minutes or until scallops are opaque.