Ireland succumbed to their first defeat at this year's World Cup when they lost to a strong South African side at the Manuka Oval in Canberra.

On a day when he would dearly have loved to have batted first, Irish skipper William Porterfield lost his first toss of the tournament and he was forced to watch as the Proteas posted their second consecutive 400-plus total in the competition.

Coach Phil Simmons made just one change to his side's line up, Andy McBrine coming in for Alex Cusack while South Africa were unchanged from the side that beat West Indies last time.

AB De Villiers won the toss and elected to bat

John Mooney and Max Sorensen shared the new ball for Ireland and the pair enjoyed contrasting fortunes early on- Mooney starting with a maiden in his first and then having Quinton de Kock caught behind by Gary Wilson in his second- still without conceding a run. Sorensen was having problems with his line however and went for 21 in his first couple as the batsmen found a foothold.

Ireland turned to Kevin O'Brien after that- the Railway Union all-rounder making a record 232nd appearance for his country, surpassing previous holder Andrew White.

With his very first ball O'Brien got Hashim Amla to on-drive uppishly when he had made just 10, but the usually safe hands of Ed Joyce failed to hang on to a sharp chance.

It was to prove a key moment in the game and when new batsman Faf du Plessis also got an escape, edging one between O'Brien at first slip and Wilson behind the stumps it looked like it wasn't going to be Ireland's day.

From there on the batting pair were in command as the bowlers struggled with the fast outfield and short boundaries. Amla was first to reach his century and was followed to three figures soon after by du Plessis.

The 247 run partnership - the fifth highest in World Cup history - was finally broken by O'Brien in the 39th over as he bowled the latter for an even time 109 (10 fours and a six). Not long after that spinner McBrine finally ended Amla's stay, but not before the opener had made a superb 159 from just 128 balls (16 fours and 4 sixes).

The Donemana youngster also claimed the prize scalp of AB de Villiers for a quick 24, but even then the Irish agony was far from done.

Rilee Roussow and David Miller batted their way through the last 8 overs with the freedom of a team with 6 wickets still intact, Roussow hitting 6 fours and 3 sixes in an unbeaten 30-ball 61 while Miller chipped in with 46 from 23 (4 fours and 2 sixes).

Together they added a frustrating 110 at the end, allowing the Proteas to post a daunting 411 for 4 in their 50 overs; just two short of the highest ever World Cup total.

McBrine was the pick of the bowlers with 2-63 although John Mooney bowled really well first up as well as he finished with 1-52. Kevin O'Brien (1-95) was the other wicket-taker while George Dockrell (0-56) and Paul Stirling (0-68) got through their overs best of the rest.

Ireland's reply hit the buffers early when Stirling edged one from Dale Steyn through to keeper de Kock and was gone for 9. It got worse soon after when skipper Porterfield was caught at mid-wicket by du Plessis off the bowling of Kyle Abbott for 12 to leave the score on 21-2.

Steyn made it 3 down in the very next over when Ed Joyce edged one into the safe hands of Amla in the slip cordon as the innings threatened to implode. The same fielder was back on the money again as Abbott found the edge of Niall O'Brien's bat- 42 for 4 and still in the Power-play and that became 48-5 when Abbott trapped Wilson in front for 14.

It was damage limitation by this point but to be fair to Andrew Balbirnie and Kevin O'Brien they did a fantastic job in stemming the tide.

O'Brien curtailed his natural instinct as Ireland looked to their net run rate and slowly but surely the pair clawed a bit back.

Balbirnie had just reached his half century however when he went for a big shot only to find Roussow in the deep and his excellent resistance ended on 58 (7 fours).

The stand was worth 81 but any hopes of a major recovery received a setback when the unlikely figure of de Villiers got Mooney to chop on to his stumps soon after.

George Dockrell was next in but Abbott returned to the attack and claimed his fourth wicket when he tempted O'Brien into a pull which was snaffled on the boundary by Rossouw. The loss of their key man for 48 (3 fours and a six) brought Max Sorensen to the middle and he and Dockrell managed to get their side to 200 before Sorensen was caught behind for a defiant 22 giving Morkel his second victim.

The end of the resistance came when Morkel then bowled Dockrell for 25- the reply finally closing on 210- a 201 run defeat in the final reckoning.

Next up for Ireland is Zimbabwe on Saturday in Hobart - a must win game for both teams as they look to gain a quarter-final berth.