Senegal needed an own-goal in extra time to edge Tunisia 1-0 and advance to the finals of the Africa Cup of Nations.
After a quiet opening, Senegal opened up the Tunisians in the 25th minute when Yussuf Sabaly rattled the upright with a curler from the left side of the area.
The Lions of Teranga took a while to get going and they had to wait until the 37th minute for their first real opening as Sadio Mane missed a gaping goal after rounding Mouez Hassan.
In an attempt to change their fortunes in the attack, Tunisia made a change at the break, as Msakni made way for Naim Sliti on the left side of the attacking area.
The Senegalese were on the edge on 47 minutes after Yassine Khenissi lobbed over the top after running through the centre of defence. Senegal continued being pinned back as Ferjani Sassi drew a low save from Alfred Gomis following Khenissi's layoff.
Wasteful expediency continued from both sides inside the 66th minute, as Khenissi failed to pounce from a one-on-one situation. Senegal livened up their structure two minutes later, as Ismaila Sarr replaced Krepin Diatta on the wide side.
Tunisia earned a penalty on 73 minutes after Koulibaly's handball in the area, a decision which was upheld after a VAR check, but Sassi failed to capitalise through a strong save from Gomis.
Five minutes later, Senegal were also given a penalty after a foul on Sarr, and Hassan outdid his opposite number with a one-handed save from Henri Saivet, which ultimately sent the game to extra-time.
The Carthage Eagles were breached on 100 minutes after Dylan Bronn cushioned the ball in o his own net after Hassan failed to parry from a free-kick.
In contrast, Tunisia were given another penalty on 115 minutes after a handball from Idrissa Gueye, but review from VAR cancelled the spot-kick as Senegal held on to claim the win for a spot in the final.