Johannesburg - Just how strongly does Springbok coach Heyneke Meyer believe Franco van der Merwe is genuinely next in line for the No 5 lock’s job?

That may be put to the test this week as South Africa aim for a 3-0 series clean sweep over England in the last encounter in Port Elizabeth on Saturday.

At the time of writing on Sunday, the national camp still awaited the outcome of scans to the injured neck of impressive Juandré Kruger, who left the field on the buggy at the start of the final quarter during the Coca-Cola Park Test here after being worryingly surrounded by medical personnel for several minutes.

The Bulls player had again been prominent up to that point in only his second Test match, and it was roughly when he and other forwards like Willem Alberts (also injured; knee problem) and Bismarck and Jannie du Plessis (substituted) left the fray that the Bok set-piece rather fell apart in the gutsy England fightback before the tourists were subdued 36-27.

With Andries Bekker, initially thought to have the inside lane to inherit Victor Matfield’s long-time slot, already on the crocked list, Springbok No 5 resources will look particularly thin if Kruger cannot make the cut for the Friendly City.

The only remaining orthodox No 5 in Meyer’s broader squad, as things stand, is 29-year-old Lions stalwart Van der Merwe.

Whether he is up to the rigours of Test rugby is a matter for conjecture, but there is obviously only one emphatic way to find out ... and a dead-rubber environment could be as good a place as any even if Meyer rightly insists he will not be handing out caps willy-nilly.

But another option available, should Kruger be ruled out, would be to consider asking his similarly blossoming partner Eben Etzebeth to switch from four to five; it is known that at his Stormers franchise the coaches believe he can be educated to serve both roles if necessary.

In such a scenario for the Boks, Flip van der Merwe, after successive intrusions off the bench against England thus far, could fit into the No 4 jersey with some assuredness - he looked up for it in his near 20 minutes at Coca-Cola Park.

Of course the availability of Alberts and fullback Pat Lambie (ankle) is also in doubt, which could mean further alterations to the starting mix for the Eastern Cape fixture.

If the hugely in-form blindside flank fails to recover in time, the reserve cupboard at loose forward is perhaps less bare.

One possibility would be to restore Marcell Coetzee to No 7, where he is very much at home despite his good recent strides on the open side, and play an orthodox fetcher and speed merchant like Keegan Daniel (impressive as a substitute for two Tests now) or even Heinrich Brüssow, a controversial earlier omission from Meyer’s squad plans.

But if the coach wants to keep up his emphasis on bruising ball-carriers, Coetzee could stay at No 6 and either of uncapped CJ Stander or Jacques Potgieter (even granted that the latter will be low on game-time after a lengthy layoff and perhaps not quite ready anyway) wear No 7.

As for the fullback situation, Frans Steyn moved there from inside centre fairly seamlessly when Lambie left the park in the 44th minute - as Meyer had always said would be the case in an emergency.

But a powerful feeling will persist for many critics that the best Bok midfield by a country mile right now is Steyn and captain Jean de Villiers, a seasoned and strong combo and both in fine nick in that specific capacity.

In that case, the coach may have to go against his instincts - which favour “physicality” across many positions - and ask slippery Gio Aplon to assume the No 15 role if Lambie is indeed laid low for the third Test.

Lots of observers would suggest that there is no special risk involved anyway - for all his lack of bulk, Aplon is a tigerish customer and could bamboozle the English defence with his twinkle-toed running if the Boks get well onto the front foot for generous periods of the game again.

Aside from any enforced injury considerations, Meyer understandably will not be too inclined to want to fiddle too much with his current brew, as he wants to secure the “sweep” and also keep building some sort of continuity among his troops.

But he also realises that some of his men have played a lot of punishing rugby recently and are showing some signs of tiredness.

He reaffirmed at the press conference on Saturday night: “We want to win every single Test match so I don’t want to make (selection) cheap. But even before this game, there were one or two guys I wanted to give chances to, to see what they can bring ... freshness, too. There are plenty of fatigued guys out there who have been playing every single week.

“So we’ll have to assess a few players. Yet we also need some continuity; we‘ve only been together as a group for two weeks, and I want some continuity, especially going into the Castle Championship.”

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