Zambia's Stoppila Sunzu, left, defends against South Africa's Tokelo Rantie, right, during their international friendly soccer match at the FNB stadium in Johannesburg, South Africa (Photo: AP)
Mbesuma, who plays his club soccer in South Africa, came on in the second half to score with a scorching shot from the edge of the penalty box in the 64th minute on Wednesday.
He might have had two more goals as the game came to an end while South Africa missed a late chance to equalise.
Zambia showed strong form with a side that featured 10 of the 11 players who won the Nations Cup in February and the champions will be among the favourites for the tournament that starts on Jan. 19.
South Africa, down to 84th in the FIFA rankings, produced another tepid performance that increases pressure on coach Gordon Igesund, who has not been able to show much improvement in the five months he has been in the job.
(For more sports news and updates, follow Ahram Online Sports on Twitter at @AO Sports and on Facebook at AhramOnlineSports)