The middle-order batsman and part-time off-spinner strained his left hamstring in the slightly nervy but eventually comfortable enough victory over perky minnows Afghanistan in Mumbai on Sunday and is probably touch-and-go at best for the next outing against the unbeaten group leaders.
The Proteas may well still have to beat both West Indies and Sri Lanka if they are to ensure onward passage to the semi-finals.
Duminy, despite his recent woes with the ball, has always been a core element of the country’s T20 plans for his cerebral batting, which generally involves working the ball around smartly in the middle phase of their innings before he explodes into boundary-seeking action himself toward the climax.
The Cape Cobras player is in decent touch, with respective scores of 54 not out off 28 deliveries against England, and then an unbeaten 29 not out off 20 balls in the latest fixture which saw the Proteas return to winning ways after a run of three defeats in T20 internationals.
His slow-bowling fare would certainly have been earmarked for use at Nagpur, where the pitch ought to be vastly different from the true, pacy surface experienced by South Africa in successive games at the Wankhede Stadium.
As captain Faf du Plessis said after the Afghanis had finally been subdued by 37 runs, the turning crumbler they will next operate on will be like playing on a “different continent”.
But if Duminy cannot make the XI against the Caribbean outfit for injury-related reasons, consider it even more certain that specialist left-arm spinner Aaron Phangiso will be required to reinforce the tweaking department.
He has been idle for both matches so far, a major-tournament trend that goes back to the 50-overs World Cup of 2015 when he failed to get an appearance at all.
Duminy and Phangiso are different players, of course, given the former’s enormously stronger all-round credentials, so one replacing the other would be no like-for-like situation.
Should Duminy be sidelined, an extra batsman would be needed, hence the likelihood that the left-handed power-hitter Rossouw - or possibly the more “nurdling”, oft-maligned Farhaan Behardien - would earn a call-up, whilst one of lower-order all-rounder Chris Morris and David Wiese would have to make way for Phangiso.
Right now Morris is the form operator of that duo, given his priceless role on Sunday in putting a halt to the worryingly riotous start by Afghanistan in their chase of a 210-run target.
Morris bowled with hostility and intensity in his first stint, and then intelligence and skill - with his reverse-swinging yorker coming into play in a pronounced way - at the death, as he notched personal best T20 international figures of four for 27.
By contrast, Wiese is currently struggling on the bowling front, leaking 47 in four overs without any wicket success against the second-tier nation, to add to unimpressive stints of 2-0-23-0 (Newlands) and 4-0-58-0 (Wanderers) against Australia recently.
Just one critic who believes Phangiso must be summoned for Nagpur is vastly experienced former SA wicketkeeper Mark Boucher, who said in the SuperSport studio after the victory over Afghanistan: “I’m still very concerned (about the SA bowling) … we need that extra spinner in Nagpur.
“Why not bring in Phangi and open with him? We can’t get any worse upfront.”
He was doubtless referring to the awful pounding various Proteas seamers have taken in the first three overs, especially, against both England (56 for one at that point) and Afghanistan (47 without loss).
Boucher’s thinking is further justified by the fact that, when New Zealand upset hosts India in the low-scoring first match of the tournament-proper at the very Nagpur, both teams opted to start out their bowling with spinners – India employing Ravichandran Ashwin and the Black Caps Nathan McCullum.
There is divided thought about the wisdom of the Proteas omitting legendary spearhead Dale Steyn, who desperately needs overs under the belt, on Sunday, and his spot is probably also tenuous as a result, rightly or wrongly, for the next match.
Albeit several days out yet, this may well be the team SA field against West Indies if Duminy doesn’t make it:
Hashim Amla, Quinton de Kock, Faf du Plessis (captain), AB de Villiers, Rilee Rossouw, David Miller, Chris Morris, Kyle Abbott, Kagiso Rabada, Aaron Phangiso, Imran Tahir.
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