Canberra - South Africa captain AB de Villiers hailed Hashim Amla as the team's "rock" after the opener cracked 159 in the crushing 201-run Cricket World Cup win over Ireland on Tuesday.
Amla reached his 20th one-day international century faster than any batsman, his career-best score coming in his 108th innings, with India's Virat Kohli the next quickest to reach 20 tons, in 133 innings.
The Proteas piled up 411 for four, the second-highest total in World Cup history.
Amla and Faf du Plessis (109) put on 247 for the second wicket while fast bowler Kyle Abbott finished with figures of four for 21 at Canberra's Manuka Oval.
"Amla is still the rock and will always be that for us. He was incredible. Hopefully that form can continue for the rest of the tour," said de Villiers, whose team are virtually certain of a place in the quarter-finals after a third win in four matches.
"It was a good game. We did it our way. We follow our game plans and the guys set it up very nicely up top for our middle order.
Amla had made 65 in the 257-run rout of the West Indies and praised his team, who have now racked up two successive totals of 400-plus.
Five different players have also made centuries in South Africa's four games.
David Miller (138 not out) and JP Duminy (115 not out) both reached three figures against Zimbabwe, while de Villiers hit 162 not out against the West Indies before Amla and du Plessis reached three figures on Tuesday.
"Fortunately we got off to a good start. We had wickets in hand so that gave us the luxury of being able to go for it, to see what happened and fortunately it paid off," said Amla.
"Any hundred is a good hundred. I'm just happy to get some runs and set it up for the boys at the back end."
Ireland suffered their first loss after wins against the West Indies and the UAE but are still in the running for a quarter-final slot with a key game against Zimbabwe coming up in Hobart on Saturday.
They complete their Pool B campaign with tough assignments against defending champions India at Hamilton on March 10 and Pakistan in Adelaide five days later.
"It was a difficult evening, they played very well. We had one early breakthrough and wanted more but then it was hard for us," said Ireland skipper William Porterfield whose evening got off to a great start when out-of-form South Africa opener Quinton de Kock was dismissed for one.
"We tried to put some pressure on, but we would've liked a few more wickets early on."
He added: "Obviously the match against Zimbabwe is a big one, so we will be looking to take the two points."