Tunisia's midfielder Youssef Msakni (L) challenges Senegal's forward Sadio Mane during the 2017 Africa Cup of Nations group B football match between Tunisia and Senegal in Franceville on January 15, 2017.
Senegal enter the match with three points, Algeria and Zimbabwe have one each and Tunisia none. The northern African neighbours meet in the first match of a double-header in southeastern Gabon.
Qualifying with a game to spare would make a welcome change for the Teranga Lions after two disastrous recent Cup of Nations campaigns.
Ranked among the favourites when Gabon co-hosted the 2012 tournament, Senegal fell to Zambia, co-hosts Equatorial Guinea and Libya and made a humiliating early exit.
Three years later they returned to Equatorial Guinea and, after beating Ghana, drew with South Africa and lost to Algeria to once again bow out after the first round.
Coach and former national team star Aliou Cisse is convinced Senegal will not commit the same mistakes this time.
"Perhaps we were overconfident in previous campaigns and believed the media hype about being among the favourites," he told reporters in this remote city.
"I believe there is more humility within the squad now -- a realisation that we are just one of many contenders to become African champions.
"We are good enough to go all the way and bring the trophy to Senegal for the first time, but many difficult matches lie ahead."
Beating Tunisia 2-0 last Sunday through goals from Liverpool attacker Mane and Kara Mbodj within the first 30 minutes was a promising start for Cisse and his squad.
Only three of the eight first-round matches played so far across the four groups have produced victories and Senegal were the only side to win by more than one goal.
However, Mane acknowledged that Tunisia were wasteful and had a shot that possibly crossed the goal-line ruled out by the referee.
"We made a great start," said the star, who finished third behind winner Riyad Mahrez of Algeria and Pierre-Emerick Aubameyang of Gabon in the 2016 African Footballer of the Year poll.
"But we have won nothing yet. The history of this competition is littered with teams who achieved great results at the start only to be eliminated long before the final.
"It is crucial that we take this tournament one match at a time. Right now our focus is solely on Zimbabwe,who are a good team."
Considered lightweights before the group kicked off because of their lowly 30th ranking in Africa and rare Cup of Nations appearances, Zimbabwe surprisingly held Algeria 2-2 in a thriller.
It could have been even better for the Warriors as they rallied from conceding an early goal to take a lead they held for 53 minutes, until Mahrez salvaged a point with his second goal.
For coach Callisto Pasuwa, one of four locals among the 16 coaches at the Cup of Nations, the result vindicated his long-held belief that Zimbabwean footballers can match the best in Africa.
"I hope that by holding an Algerian team containing Mahrez and several other stars, we can get rid of an inferiority complex we sometimes possess," he told reporters.
A concern for Pasuwa is the fitness of star Belgium-based striker Knowledge Musona, who retired injured early against Algeria.
Should Senegal defeat Zimbabwe, 2004 champions Tunisia will be eliminated if they lose to Algeria, who have also won the competition once.
The Carthage Eagles sorely missed unavailable leading scorer Yassine Chikaoui against Senegal with replacement Ahmed Akaichi squandering numerous chances.
Belgium-born Algeria coach Georges Leekens knows all about Tunisia, taking them to the 2015 Cup of Nations quarter-finals before resigning over a bonus dispute.