Youcef Belaili and Kaddour Beldjilali helped USM Alger to a 3-0 victory at home to ES Setif, whose qualification hopes were dealt a major blow on Friday.
Belaili and Beldjilali struck in the first half, while substitute Mohamed Aoudia completed the scoring at Stade Omar Hamadi de Bolghini as USM Alger - already assured of a semi-final berth - maintained their 100 per cent record in the CAF Champions League with a fifth consecutive victory.
The deadlock was broken in the 34th minute via Belaili, who placed the ball beyond ES Setif goalkeeper Sofiane Khedairia after beating the offside trap.
Beldjilali doubled the lead three minutes later, when he fired a shot across Khedairia, before Aoudia - on loan from second-tier German outfit FSV Frankfurt - came off the bench in the second half and scrambled home a third goal with 16 minutes remaining in Algiers.
USM Alger cannot be overhauled atop Group B with an eight-point lead over second-placed Al Merreikh, who travel to winless MC El Eulma on Saturday.
ES Setif are three points adrift of the second and final qualification spot, meaning Al Merreikh must lose over the weekend if the former are any chance of reaching the final four heading into next month's final group-stage matchday.
