Tunisia 1-0 Senegal
Karim Hagui outjumps Senegal's El Hadji Diouf
Jawhar Mnari saw hosts Tunisia into the semi-final of the Cup of Nations in a controversial clash in Rades.
Mnari headed home Jaziri's overhead kick midway through the second half - but the goal was only half the story.
Senegal officials invaded the pitch following the goal to protest that a free-kick should have been awarded their way earlier in the move.
And 10 minutes of second-half stoppage-time were added following a number of injuries and skirmishes.
With nearly 60,000 fans cheering them on, Tunisia began the quarter-final tie with a desire to secure an early goal.
But it was the Lions of Teranga that could have claimed the opening goal of the tie.
Roving in the penalty area, Pape Malick Diop's header from a Henri Camara free-kick only missed the post by inches.
Shaking off that early scare, the home team turned the pressure on the Senegalese.
Ziad Jaziri came close to scoring in the 19th minute, when he pounced on a rebound in Senegal's penalty area but his effort went sailing over the post.
Despite the jeers of the intimidating crowd, the Senegalese fought their way into the game, with El Hadji Diouf making a series of runs that created occasional panic in the Tunisian defence.
Yet his protests against the tough marking of the Tunisian defenders did little to sway referee Ali Busjaim.
Senegal's Lamine Sakho tangles with Slim Benachour of Tunisia
Then Lamine Sakho came close to breaking the deadlock as, sandwiched between two defenders, he outjumped both to nod a 29th-minute header that narrowly missed the roof of the net.
With the teams being evenly matched, the defending by both sides was laced with desperation.
Salif Diao received a booking in the 45th minute for pulling on the shorts of Francileudo Dos Santos, as the Tunisian forward tried to make a break for goal from midfield.
With the evening mist creating poor visibility on the turf, play in the second half became a scrappy affair.
But the Tunisians broke the deadlock in the 65th minute when Mnari, connecting with an inventive bicycle kick by Ziad Jaziri from the right side of the penalty area, nodded the ball home.
Defender Lamine Diatta failed in a last-gasp effort to head the ball off the line.
Members of the Senegalese squad invaded the pitch immediately after the goal, in apparent protest against Busjaim's failure to award a free-kick for Khaled Badra's challenge on Diouf earlier in play.
Senegal's defeat highlighted the glaring absence of their inspirational midfielder Khalilou Fadiga, who could only watch the game from the spectator stands as he recovers from the health scare that nearly scuppered his transfer to Inter Milan from Auxerre.
Meanwhile, hosts Tunisia will meet Nigeria in Wednesday's semi-final in the Rades stadium.
Tunisia: 1-Ali Boumnijel, 2-Khaled Badra, 3-Karim Hagui, 15-Radhi Jaidi, 19-Anis Ayari, 8-Mehdi Nafti, 12-Jawhar Mnari (14-Adel Chedli 88), 13-Riadh Bouazizi, 18-Slim Benachour, 5-Ziad Jaziri (9-Najeh Braham 78), 11-Francileudo dos Santos (7-Imed Mhadhebi 90+6)
Senegal: 1-Tony Sylva, 21-Habib Beye, 3-Ibrahima Faye, 4-Pape Malick Diop, 13-Lamine Diatta, 6-Aliou Cisse, 15-Salif Diao (18-Mamadou Niang 74), 19-Pape Bouba Diop, 7-Henri Camara, 10-Lamine Sakho (9-Diomansy Kamara 85), 11-El Hadji Diouf
Referee: Ali Bujsaim (United Arab Emirates)