Equatorial Guinea crushed the Elephants in Abidjan, forcing host nation Ivory Coast to rely on other results to avoid a shock Africa Cup of Nations group-stage departure.
Emilio Nsue’s double, Pablo Ganet’s 25-yard free kick, and Yannick Buyla’s late goal gave the National Thunder a memorable victory that secured first place in Group A.
After finishing third in Group A, the hosts must now focus on qualification.
The four best third-placed sides across the six groups proceed to the last 16.
Ibrahim Sangare twice had equalizers called out for the Ivorians when they were only a goal down, but the Elephants squandered numerous opportunities and were punished by their clinical opponents.
At the final whistle, some Ivorian players were in tears as they were noisily booed out by a furious partisan crowd at Alassane Ouattara Stadium following one of the most shocking Afcon surprises.
The Equatorial Guinea contingent, meanwhile, rejoiced enthusiastically after securing another seismic victory in the finals, and they will face a third-placed team from Group C, D, or E in the last 16 on Sunday.
Their finest Afcon performance was reaching the semi-finals as hosts in 2015, although they surprised everyone by finishing ahead of three-time champions Nigeria and two-time winners Ivory Coast.
Ivory Coast will have to wait until the rest of the groups end to see if their three points and -3 goal difference are enough to advance to the knockout stages.