Baciro Cande's team are assured of a top-two spot in Group A but could put on a show for supporters rooting for them in Bissau in round six of games in the section.
Match preview
While some groups in AFCON qualifying remained undecided, Group A's best two sides were confirmed with the results in the previous round of fixtures.
Guinea-Bissau's 1-0 triumph over the section's worst side — Sao Tome and Principe — in mid-June and Nigeria's late victory over Sierra Leone means Cande's team face no pressure heading into Monday's fixture.
Indeed, they could still end atop the standings if they defeat the Leone Stars in round six and the Super Eagles are beaten by the Sao Tomeans.
Djurtus could end as group winners if Jose Peseiro's team draw in Uyo on Sunday, but that would require a high-scoring victory for Cande's men on Monday.
Be that as it may, Guinea-Bissau knowing where they stand before kickoff could inspire an incredible or ordinary showing at Estadio Nacional 24 de Setembro.
As for Sierra Leone, their non-participation was confirmed in June after Kelechi Iheanacho scored at the death to seal a 3-2 win for Nigeria.
At 2-2, the Leone Stars could have forced a nail-biting final round had they completed the comeback from 2-0 down, but the Leicester City striker's goal sealed their fate.
John Keister's team will not feature at next year's AFCON, having participated at the last finals in Cameroon, with Monday's game nothing but a chance to redeem some pride.
It remains to be seen if that materialises, even if the Leone Stars could find confidence in claiming their sole victory in qualifying on their travels.
While that win came against Sao Tome, Sierra Leone's battling qualities against Nigeria saw them lead 1-0 in the eventual 2-1 loss, thus proving their capability on the road.
Guinea-Bissau Africa Cup of Nations Qualifying form:
Guinea-Bissau form (all competitions):
L
D
W
L
W
Sierra Leone Africa Cup of Nations Qualifying form:
Sierra Leone form (all competitions):
L
L
D
W
L
Advert - content below:
Team News
Jonas Mendes is expected to return in goal for his fourth appearance for Guinea-Bissau from a possible six in qualifying.
Famana Quizera has been in outstanding form for Academico Viseu this term, and the winger could make his first appearance in qualifying for Cande's men alongside several other players.
Former Tottenham Hotspur and Liverpool centre-back Steven Caulker has not made the latest Sierra Leone squad, with Keister not inviting the Leone Stars' captain, who is currently unattached.
The manager's initial squad comprised nine foreign-based players, including Mamadu Saidu Sow, who could make a debut appearance, Queens Park Rangers right-back Osman Kakay, Jonathan Morsay, and so on.
Guinea-Bissau possible starting lineup:
Mendes; Fernandes, Sangante, Ie, Mendy; Gomes, Bikel, Camara; Quizera, Dju, Mane
Sierra Leone possible starting lineup:
Sesay; Kakay, Turay, Samura, Samadiya; Michael, Kaba, Koroma, Kargbo; Williams, Fofanah
We say: Guinea-Bissau 1-1 Sierra Leone
The reverse fixture between both nations ended 2-2, and Guinea-Bissau could fall short in their aim to claim a fourth victory in qualifying for the first time, with Sierra Leone expected to hold out in Bissau.