Du Plessis and van der Dussen sum up South Africa's batting heartbreak

Rassie van der Dussen and Faf du Plessis frustrated England Gallo Images/Getty Images

It hurt when Faf du Plessis wore it on his elbow. His 15th ball, before he had scored a run, shaved his funny bone as it carried through to Jos Buttler, who appealed as loudly as the rest of his team-mates. Joel Wilson knew it was an injury, not an edge and du Plessis survived what could have been a career-ending duck.

It hurt when du Plessis wore it on his bat. His 76th ball, when he had patiently plodded his way to 29, was aimed at his head but struck him flush on the handle as he wobbled back almost on to his own stumps. He would have felt the shockwave in his hand and the signs in his head that England, and Mark Wood, were turning things up.

It hurt when du Plessis wore it on his ego. His 91st ball, which was bowled with him on the brink of equalling his highest score in the series of 36, came from Ben Stokes, bent back the bat handle and was intended to find its way to short leg. Du Plessis managed to keep it down. But he was worked up. Stuart Broad had been having words from the over before and du Plessis had had enough. He walked towards Broad, brushed Jos Buttler's shoulder on the way and then began a finger-wagging rant. The next ball he faced stayed low as it cut through him and ricocheted off the bottom edge on to his stumps.

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It hurt because maybe it was over: South Africa's fightback and perhaps his own career. This series has seen the spotlight shone on du Plessis like never before. He was called out for poor form - with 11 innings now separating him from his last half-century - and poor decision-making, particularly with the way he managed his fields in the first innings at Port Elizabeth and the first innings here.

Although du Plessis has been the effigy for South Africa's struggles, he is only a symptom of the wider problem for which one word will suffice: batting.

This is first time ever that South Africa have not put on a single total of 300-plus in a series in which they have had eight innings (in India in 2015-16, they didn't manage a score over 300 either, but only had seven innings). Their batting average of 23.15 is their fourth-worst at home since readmission and their top seven have only had it more difficult twice in that time.

You don't even need the numbers alone to tell you how bad things are, you have the names with their numbers. Dean Elgar has had eight opening partners since Alviro Petersen retired five years ago. Zubayr Hamza, who has a first-class average of 48.14, has only managed a Test average of 18.10. Since January last year, Quinton de Kock has been South Africa's most successful batsman and averages 45.90. The next most-successful batsmen is du Plessis, who averages 33.27. In that time, the other player earmarked for a significant role in the line-up, Temba Bavuma, averages 19.4.

On the domestic scene, Keegan Petersen has a first-class career average over 40 and this season Raynard van Tonder averages over 70 and Kyle Verreynne and Eddie Moore average over 50, which all sounds good, but several others (Theunis de Bruyn, Heino Kuhn, Stiaan van Zyl) have also forced their way in but then faded out. That raises questions about the quality of the domestic system, whose reputation has dwindled.

"It hurts that South Africa, who once went nine years unbeaten on the road, now struggle to win even at home"

South Africa used to have a production line of players that was considered endless so it hurts that the system is now slowing. It hurts that a country that once went nine years unbeaten on the road now struggles to win even at home and that a team that was No. 1 in the world not that long ago, is now being compared to teams that sit at Nos. 9 and 10.

All those things hurt but nothing hurts as much as when Rassie van der Dussen wore it on his heart. The 132nd ball he faced, delivered by a fired up Wood, reared up towards him; van der Dussen dropped his hands and presented his chest. The ball crashed into the right side of his sternum. Winded, he walked away, squatted to his haunches and took some deep breaths. Bat on, he seemed to say to himself. Even though it hurts, just bat on.

He was on 93 at the time and had snuck his way into the top five run-scorers of the series. A maiden Test century in a debut series in which he has been the only positive from the line-up would have been deserving after the two fifties he had already collected, especially because he was batting out of place. Van der Dussen had only batted at No. 3 in four of his 195 first-class innings before this Test, but was promoted to replace Hamza, shield du Plessis and accommodate Bavuma. All that while only in his fourth Test. He fell two runs short and nothing would have hurt more.

That alone tells you how much store South Africa are placing in van der Dussen, who was also become a mainstay of the one-day team, since making his debut last year and starring at the World Cup. It also tells you how difficult a situation South Africa are in. They are hurting. This is the third successive series they've lost, matching a run from 2004-05. Then, like now, they were defeated by Sri Lanka, India and England. Then, like now, they were between coaching regimes. The difference between then and now is that now there seems to be much more work to be done.

The appointment of former greats Graeme Smith, Mark Boucher and Jacques Kallis was hailed as their second-coming but they have proved to be no messiahs just yet. Given what they have inherited - a team in transition playing under an organisation in collapse - is going to take time to fix. For now, all they can do is take some measure of how deep and wide and long the problems are, and hurt.