Cape Town - Traditionalists, especially, may consider it a more important issue over the next couple of weeks than the relative sideshow that is the Twenty20 international series between England and South Africa.
“It” is the far from insignificant matter of whether Vernon Philander, a key member of the Proteas’ attack and valuable lower-order batsman into the bargain, regains full fitness in time for the Test series beginning on July 6 at Lord’s, as it could have a massive bearing on the eventual outcome.
Bilateral T20 series are of pretty low relevance at the best of times, other than for near-guaranteed quick-fire healthy gate takings, and the fact that the looming one comes a long way before another ICC World Twenty20 event even enters the radar only aggravates that status in many ways.
England, for example, are resting a raft of their best cross-code players - there are five new caps as a result - for the T20 phase, and South Africa are doing roughly the same by leaving out men like Faf du Plessis and Kagiso Rabada for the games, scheduled between June 21 and 25 at Southampton, Taunton and Cardiff respectively.
A few days of “switch off” for those not involved in the T20 tussles should bring mental benefits after the Champions Trophy bruising, whilst in the case of Morne Morkel, for example, an ongoing gallop in the SA limited-overs kit is instead reasonably valuable as he remains short of bowling time since his impressive comeback from injury.
Until a few days ago, South Africa’s likely four-strong specialist Test attack seemed to be taking shape nicely for the Lord’s opener, with Morkel set fair to join Radaba, Philander and budding left-arm spinner Keshav Maharaj in a solid-looking alliance.
But 31-year-old Philander is again having a worryingly stop-start time with injury mishaps of his own, to the point that it is almost a “wing and prayer” situation regarding the veteran right-arm seamer for the visitors in the lead-up.
Seldom entirely free of hamstring-type niggles these days, the stocky customer has more recently had sit-outs due to a groin problem - he played no cricket for Sussex for almost five weeks since mid-April - and now a particularly untimely ankle sprain.
Philander had just successfully negotiated a handful of four-day County Championship matches in a row, helping enormously to sharpen him for the demands of the Tests.
But then he rolled the ankle while fielding against Leicestershire at Grace Road a few days ago.
In that match, he had underlined his value - on top of his core trade - as the Proteas’ No 8 batsman in the Test XI by registering a fighting 10th-wicket stand of 83 with last man Danny Briggs, dragging Sussex much closer than once expected to Leicestershire’s first-knock total in reply.
Philander made an unbeaten 73 in almost three hours, the sort of qualities he has demonstrated before at the highest level for his country.
But it is for bowling reasons, in particular, that the Proteas badly need him firing on all cylinders in the battle to regain the prestigious Basil d’Oliveira Trophy.
Cricket South Africa seem fairly confident he will take his place for glamorous game one at Lord’s, with media officer Lerato Malekutu revealing that “he is expected to be fit for the Test series”.
Still, Philander flirts with niggles and setbacks more than he used to as the ravages of age and career work-load kick in, and even ankle sprains can be volatile injuries, with recovery times - depending on severity - ranging from a couple of weeks to several months.
It is going to be a white-knuckle ride for supporters of the SA Test cause as he fights his way back through rehab to try to ensure availability for Lord’s and beyond.
Philander, with his natural fuller length and the way he nips the ball away from right-handers, is a dreamy presence in the Proteas’ plans to topple the host nation in their own, near-unique conditions.
His value is heightened by the fact that, up to a few months ago, South Africa might have been in a position to boast at least two other pacemen with the right strengths and instincts for English pitches, in established superstar Dale Steyn and Kyle Abbott.
But Steyn has had to instead extend his recovery time from his long-term shoulder injury, precluding any activity in this series, and Abbott is now strutting his nagging, cerebral stuff for Hampshire on a much-publicised Kolpak deal.
That leaves Philander as the only genuinely proven specialist, up-to-the-bat type of seamer at the Proteas’ disposal for the Tests - any unavailability by him over the course of the series would be a major setback, despite the slightly differing attributes brought to the party by Morkel and Rabada.
When the Proteas beat England 2-0 in a three-Test series the last time they were there in 2012, Philander topped the visitors’ bowling averages with his 12 wickets at 23.66, even if Steyn (15 at 29.20) bagged more scalps.
No Philander to add to the “no Steyn” situation for 2017 hostilities?
It seems almost unthinkable.
Reports on his recuperation progress over the remainder of this month should be examined with enormous interest by South Africans ...
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