John-Joe O'Toole grabbed an injury-time winner as the Republic of Ireland secured their first win in the UEFA Under-21 Championships qualifiers against Bulgaria in Athlone.
The Watford midfielder came off the bench to head his first goal for Ireland from a right-wing cross by Eddie Nolan.
Manager Don Givens returned to this level after filling in as caretaker boss with the senior side for their Euro 2008 clash with Wales in Cardiff on Saturday.
Leicester midfielder Alan Sheehan had the first meaningful attempt on goal in the ninth minute but goalkeeper Nikolay Mihaylov parried his strike.
Mihaylov then denied Sheffield United midfielder Stephen Quinn in the 14th minute, pushing his looping strike out for a corner.
In first-half injury-time, Barnet defender Joe O'Cearuill blazed over from two yards out after the ball came back of the Bulgarian post from a deflected Anthony Stokes free-kick.
Vladimir Gadzhev had two thumping efforts in quick succession well saved by UCD keeper Darren Quigley as the visitors upped the pressure in the early stages of the second half.
Bulgaria keeper Mihaylov made another impressive save to deny Stokes in the 83rd minute.
