The defending champions were missing injured captain and goalkeeper Ronwen Williams, and star midfielder Teboho Mokoena left the field on a stretcher after a first-half foul.
Sundowns contained the threat of Wiliete striker Mabululu, the veteran Angola captain who scored three goals in the previous qualifying round.
The clubs meet again on Friday in Pretoria, with the aggregate winners advancing to the group phase of Africa’s premier club competition.
Sundowns have lifted the Champions League twice and hope to become the first South African club to win back-to-back titles.
Owned by Confederation of African Football president Patrice Motsepe, Sundowns have already secured an international trophy since the domestic season began in August.
They defeated Saudi Arabia’s Al Ahli to win the Africa-Asia-Pacific Cup. The victory set up a FIFA Challenger Cup semifinal against Mexico’s South American champions, Toluca.
The semifinal winners face UEFA Champions League holders Paris Saint-Germain for the Intercontinental Cup. Dates and a neutral venue for the three matches have not been announced.
Former African champions Mouloudia Alger of Algeria and Esperance of Tunisia lost away. Another ex-title-holder, ASEC Mimosas of Ivory Coast, snatched a late draw.
Nigerian outfit Enugu Rangers beat Mouloudia 2-0 in Abeokuta, with late goals from Kenneth Igboke and James Emo.
Earlier, Enugu goalkeeper Lucky Jimoh and Mouloudia midfielder Oussama Benhaoua were sent off, and a member of the Algerian coaching staff was also shown a red card.
Four-time champions Esperance fell 1-0 to Asswehly in neighbouring Libya. ASEC equalised in the third minute of added time through Souhalio Bamba to draw 1-1 with Maghreb Fes in Morocco. -SuperSport
The post South African club Mamelodi Sundowns began their CAF Champions League title defence with a 0-0 away draw against Angolan outfit Wiliete on Sunday in a second-round, first-leg qualifier. appeared first on New Era.