By Sunday evening in Cameroon, the first two quarter-finalists at the Africa Cup of Nations will be known.
Burkina Faso should start as slight favourites against Gabon, chiefly due to their win when the teams met ahead of the tournament.
Nigeria will then be expected to overcome a Tunisia side who qualified for the last-16 stage via the back door.
Burkina Faso vs Gabon (4pm GMT)
Burkina Faso rather scrambled through the group stage, losing their opener to the hosts before winning 1-0 against Cape Verde and drawing 1-1 with Ethiopia.
They were runners-up in 2013 and finished third in 2017, so this is far from uncharted territory and a 3-0 win over Gabon in a warm-up game for this tournament at the start of January may be a guide of what to expect from this tussle in Limbe.
Midfielder Adama Guira is urging caution though, telling the Sidwaya newspaper: "A lot of things have changed on the Gabonese side after this friendly match. Their last outing against Morocco attests to this. They are a very good team."
Gabon were unbeaten in the group stage, despite the disruption of losing captain Pierre-Emerick Aubameyang and midfielder Mario Lemina after brushes with COVID-19. A win over the Comoros was consolidated by draws with Ghana and Morocco.
That pre-tournament loss to the Stallions might be a factor, but Gabon are unbeaten in their previous two AFCON meetings with Sunday's opponents – both having taken place in the group stages (2-0 in 2015 and 1-1 in 2017).
One to watch: Guelor Kanga (Gabon)
Red Star Belgrade attacking midfielder Kanga has been a livewire for Gabon so far in the tournament, with a team-high eight shots and five chances created (one assist). It earned him a place among the substitutes in the tournament's official best team of the group stage.
Nigeria vs Tunisia (7pm GMT)
Nigeria have two players in the group stage's best XI, with centre-back William Troost-Ekong and forward Moses Simon both earning plaudits for their early performances.
Augustine Eguavoen's team were the only side with a 100 per cent winning record in the groups, and now they tackle a Tunisia outfit who only edged through as one of the best third-placed teams, having lost twice already.
These sides are meeting for the sixth time at the Africa Cup of Nations and Tunisia's only successful AFCON meeting with Nigeria came in 2004, when they progressed via penalties in the semi-finals, going on to win the competition.
Nigeria have won 12 of their last 14 AFCON games (L2), and they start this game as hot favourites.
Nigeria have had more different scorers (6) than any other team so far at this year's tournament, with Kelechi Iheanacho, Simon, Simon Chukwueze, Taiwo Awoniyi, Troost-Ekong and Umar Sadiq each scoring once.
One to watch: Kelechi Iheanacho
The Leicester striker has one goal and one assist so far, creating a team-high six chances. Such evidence points to him being a likely menace to the Tunisian defence.