Holders TP Mazembe of the Democratic Republic of Congo made a winning Group D debut Sunday by defeating CF Mounana of Gabon 2-0 in Lubumbashi.
It was a predictable outcome as Mazembe have won 10 CAF titles while Mounana were appearing in the mini-league phase of an African competition for the first time.
Both clubs are drop-outs from the CAF Champions League, having failed to qualify for the group stage of the elite African club competition.
Tresor Mputu, back at Mazembe after a spell in Angola, broke the deadlock on 17 minutes and Zambian Rainford Kalaba struck five minutes into the second half.
Victory gave the Lubumbashi “Ravens” a two-point lead after matchday 1 as SuperSport United of South Africa and Horoya of Guinea drew 2-2 in Pretoria Friday.
Mazembe, who in 2010 became the first African side to reach the FIFA Club World Cup final, are expected to win the group and successfully defend the title.
Who joins them in the quarter-finals is less obvious with Horoya slight favourites having led twice when holding understrength SuperSport.
A penalty and an own-goal helped Club Africain of Tunisia to a 3-1 Group A victory over Rivers United of Nigeria in Rades.
Bilel Ifa temporarily abandoned his defensive duties to head the hosts in front off a corner midway through the opening half.
Oussema Darragi doubled the lead with a superbly struck 45th-minute penalty into the corner that gave goalkeeper Sunday Rotimi no chance.
John Odumegwu halved the deficit through a low shot early in the second half only for Joseph Douhadji to concede an own-goal 19 minutes from time.
Rivers had a chance to set up a tense finish when awarded a penalty but Emeka Ogbugh blazed the kick over the bar nine minutes from time.
Former Confederation Cup winners FUS Rabat of Morocco lead Club Africain on goal difference after a comfortable 3-0 home win over KCCA of Uganda late Saturday.
Brahim El Bahri, Gambian Yusupha Njie and Karim Benarif scored for a club who struck seven unanswered goals last year when they hosted another Ugandan club, SC Villa.
Platinum Stars of South Africa and Mouloudia Alger of Algeria played a 1-1 Group B draw before a small crowd in mining town Rustenburg.
Brahim Boudebouda nodded in a corner on seven minutes and teenager Katlego Khunou levelled just before half-time with a close-range shot.
The draw ended a run of three home wins in the competition this season by Platinum and three away losses by Mouloudia.
Platinum and Mouloudia are two ponts behind record three-time winners CS Sfaxien of Tunisia, who overcame Mbabane Swallows of Swaziland 1-0 in Sfax.
Recreativo Libolo of Angola top Group C with Zesco United of Zambia after a dramatic 1-0 home victory over Al Hilal Obeid of Sudan.
The final whistle was imminent in Calulo when Senegalese Mamadou Diawara rose above two defenders to head into the corner of the net.
Matchday 2 is set for May 23 and 24.