- Vernon Philander's retirement leaves Lungi Ngidi as the most appealing candidate for a return to the Test team.
- Ngidi has had a stop-start Test career, and also sports only a modest tally of appearances in first-class cricket.
- His pressure-building skills make him a potentially good foil for outright tearaway bowlers Kagiso Rabada and Anrich Nortje.
Yet another once-staple, key ingredient will be missing whenever South Africa click back into Test cricket mode.
Vernon Philander has joined a gallery of glittering, hugely proven Proteas figures, either in recent months or the last couple of years, to have stepped down from international activity - or the five-day landscape, at very least.
Of the team which put up a plucky fight before conceding the fourth and final Test to England at the Wanderers in late January, resulting in a 3-1 series reverse, the bustling, naggingly accurate seam bowler is a confirmed absentee for next time ... officially now retired from SA duty at just short of 35.
As with slightly earlier, Test career-ending stars like Hashim Amla, AB de Villiers, Dale Steyn and Morne Morkel, "SuperVern" leaves a considerable void.
His statistics are remarkable ... certainly enough to place him among the pantheon of bowling legends for the country in the premier format (there's his gutsy lower middle-order batting to take into account as well; the Proteas don't have many current bowlers who wield the willow with significant success).
Philander bowed out with 224 wickets from 64 Tests - it seems a crying shame now that he only earned his first cap at age 26, thanks to Gary Kirsten's gold-value hunch - at an average of 22.32 and strike rate of 50.8.
He features at No 7 on the list of top wicket-takers in Tests for the country, with only fourth-placed Allan Donald (22.25) just pipping him to best average among the group.
It is probably safe to say that the frontline three South African Test fast bowlers at the end of last summer were Philander, Kagiso Rabada and Anrich Nortje.
The last-named two also happen to be the most hostile by instinct; they boast serious "gas" and aggression to go with various other qualities and will remain major, genuine strike factors going forward, especially as they are favourably aged: 25 and 26 respectively.
But Philander will need replacing when the Proteas eventually resume Test combat after a lengthy absence due to the Covid-19 crisis: it may yet be against West Indies in a scheduled (but probably pushed back) away series, or at home to Sri Lanka over the Christmas period.
Finding the right occupant for his shoes will be important, and particularly if head coach Mark Boucher and company believe the immediate way ahead is a formula of seven batsmen and just a four-strong attack, including likely room on most occasions for at least one spinner.
So the third pace element is a critical area for thought.
The candidate who springs most appealingly to mind - unless there are some explosive, notably big-performing finds early in the new season - is Lungi Ngidi, even if his bowling style differs a little from Philander's.
His calibre and potential (he only turned 24 in March, when the Proteas also ground to a halt activity-wise due to the pandemic) are already largely beyond doubt, although there is a caveat to that.
The broad-shouldered speedster, with the engaging personality, has overwhelmingly cut his international teeth so far in white-ball combat, where he sports 39 caps across the two shorter formats - and has made a considerable impact in a relatively short time, both for his composure under pressure and the range of his skills.
But when it comes to both Test and first-class cricket, Ngidi, who has not been short of injury setbacks, comes up fairly shy at this point for time spent in the middle in both, frankly.
His five-cap Test career has been very stop-start since that memorable debut against India at franchise home venue SuperSport Park in January 2018: he destroyed the Indian second innings, as they pursued an enticing enough target of 287, with an analysis of six for 39, including the prize, cheap scalp of touring captain and first-knock centurion Virat Kohli.
But only four, sporadic follow-up appearances have been registered, primarily because the strapping competitor has been bedevilled by fitness and related conditioning issues.
In those seven subsequent bowling innings, he has been curtailed to eight further wickets, although it is also true to say that some of the pitches he has been asked to do duty on - including on the subcontinent - have not been tailor-made for his steep-bounce attributes and useful penchant for bowling "heavy balls".
Ngidi is less than genuinely "express", but that also makes him an ideal foil, when at his best and most bodily shipshape, for the likes of Rabada and Nortje as he is a solid pressure-builder and doesn't leak runs too easily.
What Boucher and his lieutenants will be fervently hoping is that the Durban-born player can get through the 2020/21 campaign largely unscathed on the injury front after he played no part in Test activity in the last home season.
Especially pleasing, perhaps - and a key springboard for his Test return? - would be if he is able to play good doses of the CSA 4-Day Franchise Series, to get those so-valuable "miles in the legs" that fast bowlers tend to enthuse about, for their associated suitability to the intensity and stamina needs of Tests.
A reasonably educative and quite sobering stat about the young talent is that he still sports only a modest total of 17 first-class matches.
He has bowled 2 354 deliveries in that landscape, which translates to fewer than 400 overs ... or not quite 100 per year, if you calculate it from his debut (Northerns v Border) in January 2016.
A substantial upping of that volume of overs, if he can stay niggle-free in the coming summer, should be marked down as a priority, and very much in the interests of South Africa's Test side.
Because Lungisani Ngidi is still only a partially tapped gem.
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