Assale goal moves Mazembe closer to semis
Ivory Coast-born Roger Assale scored the matchday 4 winner eight minutes after half-time before a capacity 20,000 crowd at Stade Mazembe in southern Congolese mining city Lubumbashi.
Victory lifted the 'Ravens' to eight points, three more than Al Hilal of Sudan and Moghreb Tetouan of Morocco.
Tetouan shocked two-time runners-up Hilal 1-0 in Omdurman Friday through an Ahmed Jahouh penalty.
Group debutants Smouha have only three points after three consecutive defeats and are on the verge of elimination from the race for two semi-finals places.
Hilal host Mazembe and Smouha visit Tetouan in mid-August for matchday 5 games.
After a 2-0 home defeat by Mazembe two weekends ago, Smouha opted for a packed defence and counter-attacks in DR Congo.
Egyptian goalkeeper Mahdy Soliman produced superb saves from Ghanaian Daniel Nii Adjei and Malian Adama Traore to keep the game goalless until half-time.
But he was powerless when Assale spectacularly half-volleyed a weak clearance from a corner into the net.
Zambia midfielder Nathan Sinkala came off the bench during the second half for his first Mazembe appearance since being injured at the Africa Cup of Nations in Equatorial Guinea last January.