CS Constantine of Algeria came from behind twice at home to edge Ismaily of Egypt 3-2 and virtually clinch a CAF Champions League quarter-finals place.
The Algerians top Group C with 10 points, five-time trophy-holders TP Mazembe from the Democratic Republic of Congo have seven, Club Africain of Tunisia four and Ismaily one.
Constantine, who reached the group phase of the elite African club competition for the first time this season, host Africain next Saturday and one point will seal a last-eight place.
Needing maximum points to have any hope of survival, Ismaily were ahead within 13 minutes through Emad Hamdy, whose own-goal last weekend gifted the Algerians a 1-1 draw in Egypt.
Nasreddine Zaalani became the first Constantine footballer to score twice in the competition this season when he equalised in first-half stoppage-time.
Namibian Benson Shilongo put Ismaily ahead again on 50 minutes only for final-quarter goals from Nassim Yeltou and Congolese Dylan Bahamboula to win the match for the home team.
Constantine hope to emulate Entente Setif, JS Kabylie and Mouloudia Alger and bring the most prized CAF club trophy back to Algeria after a four-year absence.
With Ismaily on the way out, the chances of a 15th Egyptian triumph in the Champions League rest with Group D leaders and record eight-time winners Al Ahly.