South Africa stand-in captain Aiden Markram paid tribute to Quinton de Kock on Tuesday, describing the match-winning batsman as a "free spirit" who should be allowed "to fly".

De Kock hit 174, his third century in five matches, to lead South Africa to 382-5 in their World Cup match against Bangladesh before the team completed a 149-run rout.

For all De Kock is renowned as an outstanding shot-maker, Markram -- who himself made a stylish 60 during a stand of 161 with the left-hander -- said there was more to the 30-year-old's game than sheer natural ability.

"We all know Quinton to be the free-spirited guy that he is, but he actually has a fantastic cricket brain on him," said Markram.

"He assesses conditions really well and communicates that to us off the field even before we've walked out to bat.

"So, it adds a lot of value in that regard. And then you never want to clip his wings really. You just want to let him fly."

Heinrich Klaasen marked his return to Mumbai's Wankhede Stadium with 90, just days after his century in a 229-run thrashing of reigning champions England, as the Proteas smashed 144 runs off the last 10 overs.

Bangladesh were never in the hunt, only a hundred from 37-year-old Mahmudullah delaying a loss that had long looked inevitable.

De Kock, in what he has said will be his last major one-day international event, has now surpassed Virat Kohli as the tournament's leading scorer with 407 runs to the India star's 354.

However, he played down his innings, which followed scores of 100 and 109 during South Africa's opening two matches against Sri Lanka and Australia.

"To be honest I am a bit more tired than satisfied. It was a great day out for the guys," he said.

De Kock was then off the field for the entire Bangladesh innings following a bout of cramp, with Klaasen deputising as wicketkeeper.

"He has been amazing, I need some of the juice he is having!," said De Kock of Klaasen.

"He has been really special this year and long may it carry on."

The one downside for South Africa as they recorded a fourth win in five World Cup matches was that, having reduced Bangladesh to 58-5, they were kept waiting until the 47th over for victory.

South Africa arrived in India without Anrich Nortje after the fast bowler was ruled out due to a back injury.

But Markram was not too concerned by how they bowled late on.

"Mahmudullah played fantastically well. You are never practising in a match but we thought we would switch to 'death bowling' with him.

"But if it goes wrong, the ball tends to disappear."

Markram, again leading the side in the absence of the ill Temba Bavuma, said he expected the regular skipper to be back for the Proteas' next match, against Pakistan in Chennai on Friday.

"He has improved quite a lot but wasn't quite ready for today. Hopefully he can keep improving and be ready for Pakistan."