The game’s opening exchanges were evenly matched, with both teams failing to convert the opportunities that came their way.
Senegal, making their second successive appearance in the knockout stage of a Wafcon, showed no fear against their more established opponents, making life difficult throughout and creating their first chance as early as the third minute when Ndiaye forced Dlamini to save with her feet.
At the other end, Senegal’s 18-year-old goalkeeper Adji Ndiaye was noticeably nervous with her footwork and positioning in the opening exchanges, nearly gifting experienced striker Jermaine Seoposenwe a goal midway through the first half.
Despite that near miss, it was the Lionesses of Teranga who had the better chances up to the break, with Marseille striker Mama Diop, the game’s best outfield player, causing problems for the South African defence with her height and awareness.
The defending champions, meanwhile, were limited to a Karabo Dhlamini free-kick from just outside the penalty area that was struck weakly into the arms of keeper Ndiaye.
The second half was a physical affair as the West African underdogs continued to deny Banyana space.
It took until the 80th minute before Desire Ellis’ team created a clear chance, with an unmarked Lebohang Ramalepe missing with a header.
Diop also then had her own chance to win it, lifting a towering header from a long ball off target in stoppage time at the end of 90 minutes.
South Africa created more in extra-time, with Ramalepe initially thinking she had broken the deadlock.
The midfielder slotted home Refiloe Jane’s through-ball at the end of the opening period of extra-time, only to see the flag go up for offside.
After the break, Senegal keeper Ndiaye made her first crucial intervention, tipping over a shot from Hildah Magaia, the player whose goals broke Moroccan hearts in the final three years ago.
It looked as if a lapse in concentration would be needed to find a goal, something that appeared to happen just before the final whistle when Magaia was brought down in the box by defender Wolimata Ndiaye.
However, no penalty was awarded following a lengthy video assistant referee (VAR) check.
With neither side able to find the net, it was left to Dlamini and Mbane to write their names into South African football history, helping their team win a first Wafcon shootout following previous defeats against Cameroon in 2006 and Nigeria in the 2018 final.
But the holders will need to improve if they are to overcome a Nigeria side that is yet to concede a goal at the tournament and dispatched highly rated Zambia with ease in their quarter-final to continue the quest for a record-extending 10th title.