Cape Town – Only if they still have certain, unexpected curveballs in mind should the national selectors have reason to feel their work is incomplete as far as the Proteas’ World Cup squad is concerned.

Saturday’s securing of a 5-0 clean sweep of Sri Lanka in the ODI series, albeit secured by the Duckworth/Lewis method after the highly irksome failure of a floodlight tower at Newlands, will be viewed by many observers as having closed any remaining business by Linda Zondi’s panel for CWC 2019.

In short, 14 of the 15 players chosen for the last two fixtures in this one-sided series look increasingly likely to proceed onward to England in the second half of May … with the addition of veteran batting ace Hashim Amla, currently absent only for family illness reasons, in place of Reeza Hendricks.

Although the Sri Lankan series was well less than ideal because South Africa were never seriously stretched – that is always the best barometer of both ability and temperament – very few outsiders now seem likely to leapfrog incumbents in the group.

For one thing, the Proteas have wrapped up their 50-overs business for the season, with just three relatively low-value Twenty20 internationals to follow against the tourists.

It would require some truly special showings from an individual or two in what is left of the domestic Momentum One Day Cup (the tournament ends on March 31) to force a significant rethink by the wise men.

The major, seemingly fog-clearing development at Newlands was Aiden Markram picking an ideal moment to cement his hold on a place: when the players were forced from the field, admittedly with the host nation in firm control of the chase, the young Titans stroke-player had an unbeaten 67.

He was looking increasingly commanding even on a pitch becoming noticeably uneven in bounce and had, in fact, just eclipsed his previous best ODI score of 66 on debut against Bangladesh at East London early last season.

It brought to a pleasing close, at least for the time being, a penchant for what SuperSport commentator Mike Haysman rightly branded “lots of sparkling 20s and 30s” in the format from his broad blade, which had understandably drawn some negative sentiment from critics.

Markram was under some pressure to deliver at Newlands, bearing in mind the massive event just ahead on the calendar, and he lived dangerously early on, including surviving a sharp caught-and-bowled attempt on two and also a near run-out to a silly single.

But the 24-year-old grew and grew in authority and composure after those moments of fortune and was looking pretty well set – although there was a fair bit still to do — to finally add a century in this landscape to his well-lauded four already in Test cricket.

His excellence as a fielder also came to the fore a couple of times on the day, and that is not something to be under-estimated as the Proteas carry a few players either not renowned for their mobility or afflicted by concerns over their throwing arms after injuries.

Meanwhile, raw paceman Anrich Nortje, another relatively fringe customer, also did his World Cup claims absolutely no harm as he returned figures of two for 35 in only three balls short of a full 10-over quota at Newlands.

Pacey and aggressive, his control was also better than some more experienced seamers in the SA attack on Saturday and, after four ODIs (though all against the same humdrum foes), he now sports eight wickets at an average of 18.75 and a just as pleasing economy rate of 4.76.

The occasional waywardness of other bowlers did inspire iconic former national captain Graeme Smith to mention in commentary that he still has some reservations on that front.

Smith said he felt “Plan B” continued to look suspect in circumstances where the Proteas attack wasn’t able to simply bomb teams out with sheer pace.

“What will they do when they come up against a really flat track at the World Cup, say at a ground with small boundaries?” he asked.

Nevertheless, the SA squad looks increasingly nailed down: few surprises seem in store when their CWC hand is finally revealed toward the end of April.

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