The former South African legends carried their nations' hopes at previous ICC tournaments with Klusener's all-round capabilities characterised by his hard-hitting batting as well as Smith who opened the batting and captained the side in various competitions.
However, the Proteas have never made the final of the ODI tournament and have not progressed to the knockout stages of the tournament since the retired AB de Villiers-led side was eliminated from the semi-final in the 2015 edition following a four-wicket loss against eventual runners-up New Zealand.
"If South Africa need to be successful, they would need their 6-7 big players to really have a great World Cup," said Smith as quoted by The Cricket Times.
"If you look at top-order you have Quinton (De Kock), Temba (Bavuma) and in that middle-order, really you have really good players of spin, power players like David Miller, Heinrich Klassen and Aiden Markram that's going to be a key area for South Africa if they are going to be successful."
The former Cricket South Africa Director of Cricket raised further concern over the all-rounder role, despite some encouraging performances from Marco Jansen and Andile Phehlukwayo in the recent comeback 3-2 ODI series victory against Australia.
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"Where they fall short is, they don't have a lot of depth in batting like some of the other teams have. Who is going to be that all-rounder for them at No. 7? Marco Jansen or someone else," questioned the 42-year-old.
Lance Klusener also weighed in on the Proteas all-rounder spot, cautiously backing Marco Jansen to carry the spot during the upcoming ICC event.
"In terms of all-rounders from South Africa, I think Marco Jansen is someone that's going to be fantastic." said the former KwaZulu-Natal Dolphins legend.
"I'm sure Keshav Maharaj could do pretty much what Nicky Boje could do for us. I think a guy like Aiden Markram as well, let's not forget him.
"But I think it does help, I think your all-rounders are like your glue, they seem to help with your balance so they might be missing an all-rounder or two but it is what it is."
The former pinch-hitter nicknamed "Zulu", also refused to use the South African side's recent series victory against top-ranked ODI side Australia as a benchmark of the Proteas capabilities at the World Cup in India.
"In terms of the South Africa and Australia series, I think the conditions are totally different," he told Online Cricket Betting.
"Players were rested, rotated, certainly from an Australian point of view so it's difficult to draw any certain conclusions from. But Australia are a proper good force in World Cups. It'll be interesting to see."
South Africa will face Sri Lanka in their opening 2023 ICC World Cup clash on Saturday 7 October.