LIBREVILLE, Gabon — Senegal's blistering first 14 minutes against Zimbabwe saw it race into the quarterfinals of the African Cup of Nations on Thursday. Algeria's woeful 16 second-half minutes against Tunisia saw it sink to the brink of elimination.

Nearly halfway through the group stage, Senegal produced the most compelling argument so far for the status of title favourite when Sadio Mane and Henri Saivet scored in an overpowering start against Zimbabwe in the eastern city of Franceville.

Mane raced to touch in a shot across goal from Keita Balde in the ninth minute, making a tricky finish at the far post look far easier than it was. At full speed, Mane also managed to smoothly avoid one of the poles behind the goal holding up the net, then geared down and cruised away to celebrate. Saivet scored from a sumptuous free kick in the 14th and it finished 2-0.

Senegal could have been 5-0 up in that dizzying opening spell as it created a constant stream of chances, three of them for Mame Biram Diouf. But with Mane leading with two goals in two games, Senegal is the only team to have won both of its matches and the first to make the knockouts.

The Senegalese, who have never won the African Cup despite sending droves of talented players to Europe, head for the quarters. Algeria is heading for the exit after contributing to its own downfall in a 2-1 loss to Tunisia. Now Algeria, level with Zimbabwe on one point at the bottom of Group B, must pull off something special against Senegal in the last group matches.

In Thursday's first game, Algeria was as woeful in defence as Senegal was wonderful in attack in those decisive periods in their matches. The Algerian players won't have minded that few fans made the trek out to Stade de Franceville in the deep interior of central Africa to watch the North African derby.

Algeria captain Aissa Mandi gave away an own goal by deflecting Youssef Msakni's cross into his own net in the 49th minute.

Worse was to come 16 minutes later for Algeria: Faouzi Ghoulam helped Tunisia double its lead with an even more dreadful piece of play as he tried to head the ball back to his goalkeeper from way out near the halfway line. It dropped way short, Tunisia's Wahbi Khazri swooped on the ball, and Ghoulam fouled him from behind to give away a penalty.

Naim Sliti made it 2-0 from the spot, leaving Algeria, which got one back in injury time from substitute Sofiane Hanni, to sink to the bottom of the group.

"There are mistakes every day in football, every weekend in the big or small teams," Algeria defender Djamel Mesbah said. "We should not talk about individual mistakes. We win together, we lose together.

"This hurts the heart, especially as it's a derby, but now we think about Senegal."

Even with its highly rated forward line of Riyad Mahrez and Islam Slimani, Algeria is facing an embarrassing first-round exit and is in danger of becoming another victim of the African Cup's renowned unpredictability.

Algeria could only draw against outsider Zimbabwe in its first game, needing Mahrez, the African player of the year, to score a late equalizer.

On Thursday, Algeria finally found a way to score through substitute Hanni. His rocket shot from the edge of the area flew past Tunisia reserve 'keeper Rami Jridi and into the left corner of the goal at the start of five minutes of injury time. There was brief hope for the Algerians. Tunisia held out.

Tunisia goalkeeper Aymen Mathlouthi had been substituted, still unbeaten, before Algeria's goal, finally succumbing to a niggling injury he picked up in the first half. His departure continued a strange run of injuries for goalkeepers at this Cup of Nations.

Asselah was playing in goal for Algeria in place of injured first choice Rais M'Bolhi.

And Egypt is in dire straits with 'keepers, with 44-year-old Essam el-Hadary, who set a record this week as the oldest man to play at the African Cup, its only fit goalkeeper. Ahmed el-Shenawy limped out of Egypt's first game, giving el-Hadary his chance at the record, and third 'keeper Sherif Ekramy is also struggling. That might leave Egypt badly stretched against Uganda on Saturday.

___

Follow Gerald Imray on Twitter at https://twitter.com/GeraldImrayAP