Diakite saved spot-kicks from Oldham Athletic’s Dean Furman and May Mahlangu before Lehlohonolo Majoro missed his penalty, as Mali’s three successful attempts put them through.
Mali captain Seydou Keita’s header had cancelled out South African forward Tokelo Rantie’s first-half goal and the sides remained tied after extra-time.
The game started at a fast tempo and it was Mali who tested first with Seydou Keita‘s eighth-minute sweetly struck half-volley rising over the bar.
The host nation responded five minutes later with May Mahlangu’s unmarked header floating wide after a fine delivery by marauding full-back Siboniso Gaxa.
Buoyed on by a partisan Durban crowd, South Africa went close again, with Diakite out quickly to smother Mahlangu’s effort in the 20th minute.
Minutes later Queens Park Rangers midfielder Samba Diakite was replaced by Sigamary Diarra, after struggling with a knock sustained earlier in the game.
Despite the hosts enjoying the lionshare of posession, Mali’s left-back Adama Tamboura tested the Bafana Bafana with a cross-cum-shot in the 29th minute.
But South Africa went ahead in the 31st minute, when Thuso Phala’s scuffed attempt found Malmo’s Rantie, who slotted home his first international goal.
Mali were struggling to retain possession in midfield and former Liverpool midfielder Mohammed Sissoko was taken off early in the second half.
But in the 58th minute ex-Barcelona man Keita drew Mali level, heading Mahamadou Samassa’s cross past Itumeleng Khune from six yards out.
The Eagles almost doubled their lead minutes later when Samassa drove energetically into the area but his from a tight angle shot was well-saved.
Mahlangu gave South Africa their first real effort on goal in the second-half with a low driven shot into the goalkeeper’s body in the 79th minute.
With the game level after 90 minutes the sides embarked on extra-time, and Mahlungu made the first impression on Mali’s goal but Diakite smothered his effort.
But chances were limited for the rest of duration of added time and with both teams looking exhausted, the sides settled for penalties, with Mali, who have troubles at home, heading into the semi-finals.
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