Mauritania had never led in any of their previous eight matches at the continental finals, let alone won a match, but a first-half goal from Dellah Yaly was enough to send Algeria packing in a second successive embarrassing early exit for coach Djamel Belmadi’s side after a similar failure in 2021.

Angola took top spot in Group D with seven points from three matches followed by Burkina Faso, who they beat 2-0, on four. Mauritania, with three points, will be among the four best third-placed sides and earn a knockout spot. Algeria end fourth on two.

Algeria look a shadow of the side that lifted the trophy in Egypt in 2019. They dropped captain Riyad Mahrez to the bench against Mauritania but brought him on at half-time in a desperate bid to reverse their fortunes which proved fruitless in the end.

Mauritania took the lead in the 37th minute after a poor clearance from Algeria defender Mohamed Amine Tougai fell to Dellahi in the box and his shot beat goalkeeper Anthony Mandrea and crept in off the post.

It should have been 2-0 when Aboubakary Koita went on a mazy run in the second half and worked space for a shot but his effort was wild and spoiled what would have been one of the goals of the tournament.

Mauritania goalkeeper Babacar Niasse then produced a superb save to keep out Hicham Boudaoui’s bullet header before he managed an even better reflex stop to deny Aissa Mandi from close range.

As Algeria pushed forward in search of an equaliser, they inevitably left gaps at the back, and substitute Pape Ibnou Ba should have added a second for Mauritania late on but somehow missed the target from close range.

They were instead forced to survive 11 tense minutes of added time before being able to celebrate victory.