Guinea beat The Gambia 1-0 to move to the brink of a place in the last 16 at the 2023 Africa Cup of Nations.
Aguibou Camara scored the second-half winner, stabbing in Morgan Guilavogui’s pass to lift Kaba Diawara’s side up to second in Group C after two games.
Mohamed Bayo almost doubled the lead, lifting a shot against the crossbar from Guilavogui’s low cross.
Yankuba Minteh thought he had levelled for the Scorpions with 10 minutes left, but the offside flag was up.
The result prevented Senegal from winning the group with a game to spare after the holders made it two wins out of two by beating Cameroon 3-1 earlier on Friday.
Guinea, who held Cameroon on Monday and have four points, must avoid defeat to guarantee a top-two spot when the two West African sides meet on Tuesday (17:00 GMT).
Diawara’s men will be guaranteed to reach the last 16 for a third successive Afcon finals if Cameroon do not win against The Gambia in the simultaneous decider.