South African captain George Van Heerden smashed a century to guide his side to a win over Ireland in their U19 Cricket World Cup encounter at Brian Lara Cricket Academy in Tarouba on Friday.
South Africa won by 153 runs (DL/ method) to finish second in Group B and seal the Super League quarter-final spot.
After winning the toss and choosing to bat first, Van Heerden hit eight sixes and three fours in his 111 from 93 balls.
The Junior Proteas skipper solidified a vital 118-run partnership with Dewald Brevis, who scored 96 off 122 balls.
South Africa posted 315/7 in their 47 overs after rain interrupted play, with Reuben Wilson (2/59) and Liam Doherty (2/60) the pick of the Irish bowlers.
Ireland's response could not have got off to a worse possible start as Liam Doherty was caught off the bowling of Matthew Boast for a golden duck in the first ball of the innings.
Nathan McGuire steadied the ship with 42 from 33 balls before Andile Simelane took his wicket, with Joshua Cox and Ireland captain Tim Tector both falling cheaply to Boast.
Philippus Roux (33) provided some resistance along with Humphreys (38) but a lack of support meant Ireland were always fighting an uphill battle and they were eventually all out for 158.
Boast was the star of the bowlers for the young Proteas with three for 26 while Liam Alder also took three for 20, with Asakhe Tsaka and Simelane contributing two each.
Scores in brief:
South Africa 315/7 in 47 overs (Van Heerden 111, Brevis 96, Wilson 2/59)
Ireland 158 all out in 33 overs (McGuire 42, Alder 3/20, Boast 3/26)
Result: South Africa win by 153 runs (D/L method)