Etoile du Sahel opened a three-point gap on top of Group D with a 3-0 away demolition of Swazi side Mbabane Swallows at Mavuso Sports Centre on Wednesday.
With 2016 semifinalists Zesco United and Primeiro Agosto playing to a goalless draw in Ndola in the other match of this group, Etoile now appear to be progressing in their bid to reach the quarter-finals.
Karim Aouadhi and Maher Hannachi scored in the first half before substitute Mohamed Chermiti sealed victory for the 2007 African champions in the 71st minute, just six minutes after coming on for Egyptian striker Amr Marei.
Arriving in Manzini tied on four points with Swallows but enjoying a slight lead on the number of goals scored, Etoile were ruthless to seperate themselves from the rest.
The result ended Swallows’ fine start to their debut Champions League group campaign, in which they had avoided defeat in the two other matches.
Swallows consolation is that they remain in second position, thanks to the draw in Ndola.
Etoile could further increase their lead when they host Swallows in the return fixture at home in Sousse next week.
While the Tunisians celebrating, it was another afternoon of struggle for Zesco and Primeiro Agosto who remain winless after three rounds of matches.
The goalless draw at the Levy Mwanawasa Stadium left the two sides with two points each ahead of the second leg in the Angolan capital Luanda next week.
Hopes of reaching the last eight is however not lost with victory for any of the two strugglers, and this places the winner in second position given that Swallows lose in Tunisia.
What could be worrying for Primeiro Agosto is that they have failed to score in the last two matches and have just one goal in their Champions League group stage account.
Hosting the Zambians who managed a goal in their 2-1 away defeat to Etoile du Sahel in May could be another concern for Primeiro Agosto.