Cape Town - With just 15 days remaining between now and
If Amla plays, though, then including Markram becomes complicated.
In that scenario, Rassie van der Dussen emerges as the man most likely to miss out, which would be harsh.
He has only played 9 ODIs for his country, but Van der Dussen has done more than enough in that time - he averages 88.25 - to suggest that he is World Cup ready.
It is now beginning to look like when South Africa play their two warm-up matches against Sri lanka (May 24, Cardiff) and West Indies (May 26, Bristol) there will be players fighting for places.
Those two fixtures could effectively serve as Amla's World Cup trial.
"Those two games become very important for somebody like Hash, for instance, who hasn't played for a while," Gibson told media in Cape Town on Tuesday.
"We'll be taking those games very seriously."
Ideally, the Proteas should know what their strongest top order is at this stage, but one positive is that in Markram they have a player flexible enough to give them several options.
It is a long tournament, after all, so change is likely.
"We have a number of guys who can bat in various positions," Gibson said.
"We haven't sat down and said where everybody is going to bat yet.
"Aiden is a top three player so I'm sure if he plays he will play there. He can bat further down, too, and it's good to have somebody dynamic like that."
"If Hash opens the batting we can play him in the middle order. It gives us a lot of options going forward."
Despite his recent returns, Markram still averages just 29.58 from his 18 ODIs while Amla averages 49.74.
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