The Leopards eliminated seven-time winners Egypt in the round of 16, while Syli National ended a losing run in the competition's first knockout by defeating Equatorial Guinea.
Match preview
DRC are yet to win a game in Cote d'Ivoire, but the Leopards find themselves in the last eight of the continental showpiece, defeating Egypt — who equally failed to claim a victory in regulation time before their elimination — on penalties.
Lionel M'Pasi was the hero for Sebastien Desabre's men, converting from the spot after Pharaohs goalkeeper Mohamed Abou Gabal hit the woodwork in the sudden-death rounds, and the shot-stopper took advantage by dispatching his with ease.
The upshot of eliminating Rui Vitoria's men means the Leopards won their first knockout game at the Cup of Nations since 2015 when they made it to the semi-finals and ultimately ended third.
That eventuality is far from assured this time, with Desabre's men unlikely to go deep if they retain the overreliance on extra time and penalties, even if Egypt showed it could be done at the previous finals.
Having not claimed the win in regulation time, the Leopards seek their first knockout stage victory since a quarter-finals 4-2 win over Congo at the 2015 Cup of Nations.
As for Guinea, the last-gasp Mohamed Bayo header ended Syli National's extended run without a knockout stage win in their history at the finals.
The victory came following Federico Bikoro's 55th-minute dismissal for the Equatoguineans and Emilio Nsue's missed penalty, preventing extra time for Kaba Diawara's troops.
Interestingly, Guinea progressed to the knockout rounds as the competition's best third-placed side, and they go into the quarters as the only remaining side from Group C still in the competition, after Senegal and Cameroon were eliminated by Ivory Coast and Nigeria, respectively.
Having ended their hoodoo of the knockouts, Diawara's men now seek to make the AFCON 2023 semis, where they could face Mali or the tournament hosts.
Despite scoring three times in their four games (two in the group stage), Syli National aim to be productive in the final third this time to avoid exiting in the quarters.
Congo DR Africa Cup of Nations form:
D
D
D
W
Congo DR form (all competitions):
D
L
D
D
D
W
Guinea Africa Cup of Nations form:
D
W
L
W
Guinea form (all competitions):
L
W
D
W
L
W
Team News
Edo Kayembe has missed every DRC game at the Cup of Nations, and it remains to be seen if the midfield man is back in action for the last eight.
Gael Kakuta was a significant miss for the Leopards in the round of 16, but the former Chelsea man could return for Friday's fixture.
Yoane Wissa and Cedric Bakambu have not delivered the goods so far, with the latter missing a group-stage penalty against Morocco, further complicating Desabre's plans.
The Guineans have battled fitness issues with Naby Keita and Serhou Guirassy, with the latter's absence weakening their potency up top.
Ilaix Moriba is doubtful after sustaining an injury against the Lions of Teranga — the midfield man was not in the round of 16 squad.
Diawara could revert to a 4-2-3-1, with Syli National's top men returning to the XI for the first time since being handed starts against Senegal in their final group game.
Congo DR possible starting lineup:
M'Pasi; Kalulu, Mbemba, Batubinsika, Masuaku; Pickel, Moutoussamy; Bongonda, Kakuta, Wissa; Bakambu
Guinea possible starting lineup:
Kone; Diakite, Diakhaby, Jeanvier, Sylla; Konate, Diawara; Guilavogui, Keita, Sylla; Guirassy