Morocco and Tunisia are braced for an early showdown as both teams hope to lead the North African challenge at the African Cup of Nations in the absence of the region's dominant force, Egypt.

The teams will get an immediate indicator of which is better off when they meet in their opening match in Group C on Monday, a game that could be a fiery start for the fierce rivals.

After co-host Gabon and Niger open the Gabonese side of the tournament at the Stade de l'Amitie in Libreville, Morocco and Tunisia face off in a showdown that may define their championships.

The winner is a good bet to top Group C and enjoy an easier run to the semifinals. The loser could be left to scrap for second place in the group and a possible meeting with likely Group D winner Ghana - one of the favorites - in the quarterfinals.

It puts the North African contenders in what's almost a must-win match straight away.

''We have our first match against Tunisia and it is very important because they are one of the two favorites of the group,'' Morocco's Belgian coach Eric Gerets said.

Morocco goalkeeper Nadir Lamyaghri added: ''If we manage to win three points against Tunisia, we then have a 50 percent chance to make it to the quarterfinals.''

Gerets accepted the games against Gabon and Niger will also be testing. Gabon will be boosted by home support, he said, while Niger ''will play freely'' as the group underdog at its first-ever African Cup.

However, there is no denying the crucial importance of the Morocco vs. Tunisia clash for the teams' morale.

The Moroccans and Tunisians are both buoyed by an emergence of new talent at the 2012 continental championship, but Morocco has relied on a foreign-based contingent while Tunisia has looked closer to home and Tunis club side Esperance for the core of its squad.

Likewise, Morocco has put faith in Belgian tactician Gerets while Tunisia is guided by former national player-turned coach Sami Trabelsi.

Trabelsi, a squad member at the African Cup of Nations in 1996 when Tunisia lost the final to host South Africa, has not been afraid to announce his team as a surprise contender for the title - even with most predicting an Ivory Coast-Ghana decider.

''This edition reminds me of the one that we played in South Africa,'' Trabelsi said. ''Nobody was expecting our team to reach the final. I think this year we have a team that is capable of going very far in this Cup of Nations.

''In attack we have one of the best generations in our history. We have players who can make a difference at any time. They have considerable technical qualities.''

Tunisia has the country's leading scorer Issam Jemaa, fellow striker Amine Chermiti and Esperance's Oussama Darragi in midfield, who was voted best player in Africa last year.

Morocco is led by Arsenal's Marouane Chamakh up front, alongside forwards Youssouf Hadji of Rennes and Queens Park Rangers' Adel Taarabt.

Lamyaghri, the experienced goalkeeper from Casablanca club Wydad, said he had fully recovered after a layoff because of a shoulder injury. He was a major doubt for Morocco's campaign a few weeks ago.

''I am 100 percent ready because I played three successive games in the Moroccan championship,'' he said. ''But the final choice (over whether I play) remains with the coach.''

Morocco has not won the African Cup of Nations since its one title in 1976, while Tunisia was the last team to lift the trophy before Egypt's three successive triumphs from 2006-10.

Tunisia beat Morocco in that 2004 final, which was also the last time the teams met in the tournament. That memory is certain to inspire both countries - one for revenge and one for a repeat - when they meet again next Monday.

''It is true that there is an expectation from the Moroccan people,'' Gerets said. ''We are aware of this and for ourselves and for the people we must do a good Cup of Nations and aim as high as possible.''