The Nzalang Nacional had to win to progress from Group A at Gabon's expense and were on their way once former Real Madrid player Balboa won and then converted a 55th-minute penalty. Iban Edu then came off the bench to make sure of the victory in the 86th minute as Esteban Becker's unlikely side kept alive their dream of going all the way on home soil.
There were scenes of unbridled joy among the Equatorial Guinea players at the final whistle, with some breaking down in tears. They go through as runners-up in Group A behind Congo, who defeated Burkina Faso 2-1 in Ebebiyin in the day's other game. And Equatorial Guinea will now take on the winners of Group B in the last eight in Ebebiyin next Saturday.
Felipe Ovono in the home goal somehow kept out an Aubameyang header and then denied Frederic Bulot to ensure that the scores remained level at the interval. The home 'keeper was again called into action at the beginning of the second half to keep out net-bound free-kicks from both Aubameyang and Bulot, and Equatorial Guinea took full advantage to open the scoring ten minutes after the restart.
Balboa went down in the box under a challenge from Lloyd Palun as he attempted to latch onto a return pass from Bosio and was awarded the penalty. Balboa dusted himself down before rifling the spot-kick high into the top left-hand corner of the net despite Didier Ovono diving the correct way.
Bulot was unable to convert an Aubameyang ball from the left moments later as Gabon almost equalised, but the home side remained a constant threat on the break and Balboa was denied by Didier Ovono when left with just the 'keeper to beat.
However, substitute Iban made no mistake four minutes from time, converting the rebound after Emilio Nsue's shot was saved at the end of a flowing move to seal the hosts' place in the last eight.