Cameroon responded belatedly when Jean-Charles Castelletto powered home a header from Olivier Ntcham’s 83rd-minute cross and Georges-Kevin Nkoudou has guilty of a glaring miss before Mane scored, but Rigobert Song’s side will head into its final group fixture against Gambia with just a single point to its name.
Senegal went ahead after the Cameroon defence failed to deal with Pape Sarr’s 16th-minute corner.
The ball was fed back in to Sarr after goalkeeper Andre Onana had punched it to the edge of the box and he drilled in a low right-footed shot which took a slight deflection off Frank Anguissa and flew into the net.
The Indomitable Lions did not muster a single attempt on goal in the opening 45 minutes and might have fallen further behind six minutes before the break but for Enzo Tchato’s block after Lamine Camara had put Mane in on goal.
Aliou Cisse’s men continued to make the running after the restart, but Olivier Kemen got a sight of goal at the other end, only to loop his 55th-minute header from a deep free-kick high over.
Cameroon’s fortunes took a further turn for the worse with 19 minutes remaining when Sarr turned provider with a low cross for Habib Diallo to make it 2-0 from close range.
Castelletto gave Song’s side hope with seven minutes remaining and it should have been level when Nkoudou headed inexplicably wide in stoppage-time before Mane wrapped up the points.
The result meant that defending champions Senegal have now booked a place in the second round of the competition while the Indomitable Lions of Cameroon are presently occupying the third position and would have to defeat Gambia to start a chance of qualifying to the the next stage of the competition.
However, Guinea defeated Gambia courtesy of Aguibou Camara’s second half lone strike to earn the Guineans all three points and a place in the second position of the group C.
Recall that the Syli national of Guinea also drew 1-1 with Cameroon in their first group C opener.
Guinea now has four points in in two games and look set to have secured qualification into the group stage of the competition.