Substitutes Joe Kelly and Ian King climbed off the bench to grab the goals in a 2-0 triumph at Wellingborough Whitworth.
Star were well below par in the opening period of the first qualifying round tie, but the introduction of Kelly (pictured above) just before the hour sparked them into life.
He could have scored with his first touch when seeing a lob agonisingly dip inches over the bar, but he made amends moments later when sliding in to convert a James Hill-Seekings delivery.
And Star clinched their passage with eight minutes remaining when fellow replacement King rifled in from the edge of the box after a corner had been cleared into his path.
Star's reward is a home clash against Thurlow Nunn Youth League West Division rivals Godmanchester Rovers in the second qualifying round. That tie is to be played on Monday October 6 at the Mick George Arena.
Star Under 18s: Dunmore, Horn, Colbert, Ilsley, Redhead, Warrener, Roberts (Kelly), Darani, Williams (Johnson), Hill-Seekings (King), Bick. Unused subs: Rey, Pululo.