After hosts Zesco United of Zambia won the first matchday 1 game Saturday, Wydad Casablanca of Morocco set a trend of victories by visiting teams in the premier African club competition.
Sundowns, eliminated in the final qualifying round only to be reinstated when V Club of the Democratic Republic of Congo were disqualified, scored two superb goals. Mabunda struck in the first half with a long-range shot and Billiat dribbled past several defenders before slipping the ball into the net during the second half.
An early headed goal by Bassem Morsy earned Zamalek a 1-0 win in Nigeria over Enyimba, who scored 10 goals in three home matches during qualifying. Both teams battled to pass accurately on a pitch soaked by torrential rain in the southeastern city of Port Harcourt.
Zesco upset record eight-time African champions Al Ahly of Egypt 3-2 and Wydad won 1-0 at ASEC Mimosas of the Ivory Coast in other games.
Matchday 2 fixtures are scheduled for June 28-29.