CANBERRA: Hashim Amla and Faf du Plessis hit centuries, while Dale Steyn shone in his 100th one-day international, as South Africa showcased their prowess with a 201-run rout of Ireland in the World Cup on Tuesday.

Amla scored 159 off 128 balls to become the fastest man to reach 20 ODI centuries and du Plessis made 109 as the Proteas piled up a massive 411 for four after taking first strike at Canberra's Manuka Oval.

Steyn put aside worries of mountain fires near his home in Cape Town as he bowled a hostile opening spell to wreck Ireland with two wickets in his first three overs.

The fast bowler, who had grabbed just three wickets in South Africa's first three pool matches, finished with two for 39 and Kyle Abbott grabbed four for 21 as Ireland were bundled out for 210 in 45 overs.

The Irish were reduced to 21 for three by the fifth over and slipped to 48 for five by the 11th before Andy Balbirnie (58) and Kevin O'Brien (48) led a late revival by adding 81 for the sixth wicket.

South Africa's third win in four matches brought them level on six points with defending champions India, who have played one less match, in Pool B.

Ireland have four points from three games.

Amla and du Plessis put on 247 off 217 balls for the second wicket to lift South Africa to the second highest total in World Cup history, just two runs behind India's record 413 for five against Bermuda in 2007.

It was the second successive 400-plus total for the Proteas in the current tournament, following their 408 for five against the West Indies in Sydney last week in which skipper AB de Villiers hammered 162 off 66 balls.

With victory almost assured, de Villiers used eight bowlers -- including himself -- ahead of tougher games.

Amla smashed 16 boundaries and four sixes, while du Plessis contributed 10 fours and a six in a scintillating display of attacking batting on a dry, run-laden pitch.

Both batsmen were dismissed in the space of three overs, but Rilee Rossouw hit an unbeaten 61 off 30 balls and David Miller chipped in with 46 not out as South Africa hammered 131 runs in the last 10 overs.

Prior to Amla and du Plessis's stand, Ireland were initially in the game when seamer John Mooney, whose first two overs were maidens, had Quinton de Kock caught behind for one.

South Africa would have been in further trouble when Kevin O'Brien, who became Ireland's most-capped player on Tuesday with 87 ODI appearances, came on in the sixth over and nearly claimed a wicket with his first ball.

Amla, then on 10, flicked uppishly to short mid-wicket where Ed Joyce, normally a safe catcher, dropped the ball after getting both hands to it.

Ireland paid dearly for the lapse as seamer Max Sorensen conceded 24 runs in one over, with Amla smashing him for two sixes and a four and du Plessis lofting him for six.

In the second powerplay, Amla took 26 runs off one Mooney over with a sequence of two, four, four, six, four, six. An additional run came off a no-ball.

Amla's career-best century, in his 108th innings, was a new record, with India's Virat Kohli being the next fastest to reach 20 ODI hundreds in 133 innings.

South Africa next play Pakistan in Auckland on March 7, while Ireland take on Zimbabwe in Hobart the same day.

Team Lineups

South Africa: Hashim Amla, Quinton de Kock, Faf du Plessis, AB de Villiers (captain), Rilee Rossouw, David Miller, Farhaan Behardien, Dale Steyn, Kyle Abbott, Morne Morkel, Imran Tahir.

Ireland: William Porterfield (captain), Paul Stirling, Ed Joyce, Niall O'Brien, Andy Balbirnie, Gary Wilson, Kevin O'Brien, John Mooney, Max Sorensen, George Dockrell, Andy McBrine.

Umpires: Steve Davis, Australia, and Ranmore Martinesz, Sri Lanka.

Third Umpire: Ian Gould, England.

Match Referee: Roshan Mahanama, Sri Lanka.