Youssef Msakni struck as Covid-hit Tunisia stunned 10-man Nigeria 1-0 to advance to the Africa Cup of Nations quarter-finals.
The Tunisia captain powered home a low shot from outside the penalty area two minutes into the second half to bundle Nigeria out of the tournament.
Nigeria had been the only side to win all three of their games in the group phase and were overwhelming favourites as Tunisia battled without seven players, who were isolating because of Covid-19.
But Tunisia, who also had to do without coach Mondher Kebaier because of Covid-19, advanced to meet Burkina Faso in next Saturday’s quarter-final in Garoua.
There were few chances in the game with Tunisia producing a stout defensive performance and looking for counter-attacking opportunities.
Nigeria were unable to get any flow to their play, despite having beaten Egypt, Sudan and Guinea Bissau in their earlier games.
They were reduced to 10 men when Alex Iwobi was sent off for a dangerous tackle in the 66th minute, seven minutes after coming on.