Cape Town - The difference between them in levels of experience is humungous.
But Wiaan Mulder effectively assumes the “JP Duminy role” in the early part of the one-day international series against Sri Lanka shortly ... and it may even be viewed as a stepping stone to fulfilling the duty on an emergency basis at the World Cup.
The Proteas brains trust’s almost indisputable preoccupation with a brimful bowling unit, to the detriment of specialist batting, has already made it pretty obvious that Mulder, just turned 21, will occupy the important No 6 berth in the first three ODIs against the shock Test series-winning tourists.
Those matches are scheduled for the Wanderers on Sunday (10:00), and then onward to SuperSport Park on Wednesday and Kingsmead the next Sunday before any alterations might be done to the 14-man squad for the final two clashes in the five-game series.
But working out the SA batting line-up - an area that has cried out for strengthening of late, whether at Test or ODI level - is not too hard to do, given the structure of the current party.
The mere five, out-and-out batsmen will also occupy the prime slots, in this likely order: Quinton de Kock, Reeza Hendricks, Rassie van der Dussen, Faf du Plessis and David Miller.
Considering the expressed desire of head coach Ottis Gibson and skipper Du Plessis to develop Mulder into a more batting-geared all-rounder (most of the versatile players lean closer toward bowling), he is clearly earmarked for No 6 at the outset of this series; nobody else obviously springs to mind in the squad.
It is the sort of ODI terrain - either five or six, to be more accurate - Duminy is hugely familiar with, including as a partial element of the bowling plans with his useful off-spin, but the huge snag is that the nearly 35-year-old veteran has had a delayed recovery from his serious right-shoulder injury.
The earliest he will return now is for games four and five (St George’s Park and Newlands) and that is cutting it fine to confirm his readiness for the World Cup in the UK from late May as the Proteas have no further ODI obligations until then.
Considering his richly proven credentials (192 caps, 5,016 runs and 67 wickets), Duminy was intended to be a key, street-smart balancer in the line-up at CWC 2019 but his participation is clearly not a cut and dried thing.
He was still struggling with his throwing a few days ago, and that is an important consideration because several other Proteas stalwarts - like Du Plessis and Dale Steyn - have had major right-shoulder sagas previously and sometimes need to exercise a bit of caution in the department.
This turns a significant spotlight on Mulder, the fresh-faced Lions customer who Gibson has seemed, for at least a year, significantly keen to fast-track.
As things stand, it is a slightly scary thought that the Proteas, already characterised by a long tail, will be fielding a No 6 with a top score in ODIs thus far of 19 not out from eight innings (57 runs at 14.25).
But Mulder’s knocks have largely been at less demanding Nos 7 or 8, and include a few not-outs with minimal time left in the innings, so it would be grossly unfair to brand him a flop to this point.
Nevertheless, the likely promotion to No 6 at the Bullring will be a great opportunity for Mulder to demonstrate his mettle as a stroke-player.
His fledgling first-class career already shows statistical promise, as the former SA under-19 star boasts a batting average in that landscape of 40.30 from 21 outings and 61 scalps at 23.42.
But if he doesn’t come off meaningfully at the crease against the Sri Lankans, it will lessen the likelihood that he covers for Duminy (assuming it becomes more consistently necessary, of course): the Proteas may find it more comfortable to simply install a more specialist extra batsman at six and leave the bowling duties almost entirely to their “bottom five” in the line-up.
At least Mulder sets out on this educative experiment, as an almost certainly elevated batting factor, at his home ground this Sunday ...
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