Veteran Youssef Msakni scored to give previously unimpressive Tunisia a shock 1-0 triumph over 10-man Nigeria in Garoua on Sunday in an Africa Cup of Nations last-16 match.
The north Africans now face Burkina Faso, who eliminated Gabon after a penalty shootout, in the quarter-finals of the flagship African tournament next Saturday.
Nigeria had a good chance to level at the start of added time when substitute Umar Sadiq got behind the defence and fired across goalkeeper Bechir Ben Said only to see his shot trickle wide of the far post.
Msakni struck on 47 minutes and Nigerian hopes of levelling were dealt a major blow midway through the second half when Alex Iwobi was red-carded.
Nigeria started as favourites to reach the quarter-finals having won all three group matches in the northwestern city, with record seven-time champions Egypt among their victims.
Tunisia, making a record 15th consecutive Cup of Nations appearance from 1994, fell to Mali and minnows Gambia in the first round and squeezed into the knockout phase among the four best third-placed teams.
While Nigeria were able to choose 12 substitutes, Tunisia could manage only eight due to a coronavirus outbreak in the camp.
Also missing due to Covid-19 was Tunisia coach Mondher Kebaier, who was isolating in coastal city Limbe at the other end of the central African country.