Algeria became the final African side to secure their place in South Africa next summer after Antar Yahia's goal was enough to beat Egypt in their winner-takes-all showdown in Sudan.
The two sides were facing each other for the second time in four days after Egypt scored a late, late goal on Saturday to end level with their bitter rivals at the top of their qualifying group.
But after earning a second chance, the Pharohs could not reproduce their Cairo efforts and were second best for much of the game.
The crucial moment came in the 40th minute when Karim Ziani lofted over a superb ball and Yahia smashed home, sending half the crowd in Khartoum wild.
Egypt pressed for an equaliser in the second half but failed to find any quality in the final third and as time ran out their attempts became more desperate and wayward.
The referee's whistle sparked scenes of joy for the Algerians, with many of their players climbing onto the crossbar of one of the goals to celebrate.
Coach Rabah Saadane said: "We played with heart and that's what made all the difference."
