France-based Bongani Zungu scored as unimpressive South Africa laboured to a 1-0 Africa Cup of Nations Group D win over Namibia Friday to keep alive hopes of making the second round.
However, to book a last-16 place the winners will probably need at least a point against leaders Morocco, who defeated the Ivory Coast 1-0 in the first match of a double-header.
Already qualified Morocco have six points, the Ivory Coast and South Africa three each and Namibia remained pointless after two solitary-goal losses.
With Ivory Coast set to beat Namibia Monday, the best South Africa can realistically hope for is one of four places reserved for the best third-place finishers.
It looks increasingly likely that teams coming third in the six groups will need a minimum of four points to be among the quartet that survives.
Zungu netted on 68 minutes with a header off a corner to settle a match that lacked the quality of the clash between Morocco and the Ivory Coast.
South Africa made four changes to the team that started in a loss to the Ivory Coast four days ago, including the shock demotion of goalkeeper Ronwen Williams, who was outstanding.
He was replaced by Darren Keet and Hlompho Kekana, Zungu and Sibusiso Vilakazi were also promoted with Kamohelo Mokotjo, Lebohang Maboe and injured Dean Furman dropping out.
Namibia coach Ricardo Mannetti included Egypt-based Benson Shilongo for Absalom Limbondi in the lone change to the side that unluckily lost to Morocco after conceding a late own-goal.
South Africa had a chance to go ahead on 16 minutes, but Vilakazi blazed over at the Al Salam Stadium in the Egyptian capital after a Themba Zwane backheel gave him a clear sight of goal.
Mannetti must have been pleased when the 21st minute passed as he was part of the side trailing South Africa 4-0 at that point when they last met 21 years ago in Burkina Faso.
Now retired Benni McCarthy scored all four Bafana Bafana (The Boys) goals in the victory and how England-born coach Stuart Baxter must have longed for someone similarly clinical in this match.
South Africa had plenty of possession, but lacked creativity in the final third of the pitch and their frustration led to many hopeful, long-range shots.
Namibia, with four South Africa-based players in the line-up, held their own and did not resemble a side 41 places lower in the world rankings.
Percy Tau, of whom much had been expected in this Cup of Nations, could have broken the deadlock as half-time approached but a weak shot was comfortably saved by Loydt Kazapua.
Deon Hotto came close to putting Namibia ahead midway through the second half after Keet spilled a cross and the Namibian had his shot cleared off the line by Buhle Mkhwanazi.
Almost immediately, South Africa forced a corner and Zungu from Ligue 1 outfit Amiens rose unchallenged in the middle of the six-yard box to nod the former champions into the lead.