You have to hand it to England and South Africa. They may not often be the best two teams in the world, but when they go head-to-head - at whatever stage of their respective team developments - sparks cannot help but fly. The Port Elizabeth Test will be the 50th encounter between these two sides since South Africa's readmission in 1991, and they go into the match all-square by almost any metric you'd care to analyse.
England have won 16 Tests of those previous 49, as have South Africa. England have won four series out of 11, including two at home and two away, as have South Africa. And only twice in all those series has either side emerged victorious by more than a single result: sure enough, it's one apiece on that front too, with South Africa's 2-0 win in 2012 matched by England's 3-1 scoreline five years later.
All of which is a roundabout way of saying: presume nothing about the direction of this latest contest. We are locked at one Test all after a gloriously immersive contest at Cape Town a fortnight ago, but the two sides have been teetering on the brink of crisis all season long, and that inherent instability is surely not about to leave the arena as we enter the fraught final exchanges of another absorbing tussle.
In any ordinary context, you'd assume that England were now the team in the ascendancy - their 189-run win at Newlands was more comprehensive than it felt in that fraught race against time on the final day, thanks in no small part to the irresistible impact of the newly crowned ICC Player of the Year, Ben Stokes. When he's on song, as he spent most of 2019 demonstrating, his presence alone can atone for a multitude of shortcomings elsewhere in England's ranks.
Which is just as well, because their stocks have been depleted yet further in the days since England began to meander down the Garden Route and take up residence in the Eastern Cape. The prognosis on James Anderson had looked bleak from the moment he bowled just two overs on the final afternoon at Newlands, but confirmation of a cracked rib robs England of their iconic attack leader for the second time in six months.
And Tuesday's sad news of Jack Leach's departure from the tour was a reminder of the virulent sickness bug that has stalked the whole squad since the opening days of the tour. Joe Root caused another scare when he missed training earlier in the week, although he seems now to be on the mend, but further accidents and incidents never seem far from the surface. Just ask Rory Burns, whose seemingly innocuous football injury on the eve of the second Test has escalated to surgery and a four-month lay-off.
Would England swap their position for that of South Africa, however? The character the hosts showed in surging to victory at Centurion in December gave way to a more flimsy display in the New Year, as if to confirm that the depth of the crisis gripping Cricket South Africa in the build-up to the series was not something that a change of management and a few hearty team bonding sessions could remedy.
The most fundamental concern right now swirls around the future of South Africa's captain, Faf du Plessis. His distracted dismissal at Cape Town, caught on the slog-sweep for 19 when defence was the only objective, capped a grim run of form in which he's managed 79 runs in his last seven innings, with his most recent century more than 12 months ago. At the age of 35, predictable questions have begun circling, and will surely only get louder if his side cannot get something out of the remaining two Tests of this campaign.
Transformation issues invariably complicate the picture for South Africa too. The team's official vice-captain, Temba Bavuma, remains on the fringes as he works his way back to form after injury, and his absence leaves the team short of meeting their transformation target - calculated on average over a season - of fielding six players of colour of which at least two must be black African.
The team's pragmatic concerns may well hold sway in the short term - a series win over England would be a boost for cricket throughout the country irrespective of the team's current make-up - but the off-field pressures are real and unavoidable. All of which ensures there's all to play for in the coming five days. As there always is when these two flawed outfits come up against one another.
(last five completed matches, most recent first)
South Africa LWLLL
In the spotlight
Remarkably, it's been nearly a year since Mark Wood's last Test appearance. But what an appearance. At St Lucia in the final Test of England's series defeat in the Caribbean, Wood unleashed his offerings with the fury of a pelota ball - all fizzing angles and searing speed, as he served up a spell of fast bowling as pure and nasty as anything that an England quick has produced since Devon Malcolm wrecked South Africa at The Oval in 1994. He said at the time that he felt he'd arrived as a Test cricketer - but alas, he was unable to prove it further after picking up a side strain during the World Cup final, an injury that ruled him out of the Ashes and left him targeting the back end of this trip for a recall. Happily, Wood is not the sort of chap to dwell on his injury setbacks, and he rarely holds back in anticipation of a relapse. By all accounts, he's been rapid in the nets in recent days, and looks likely to get his chance ahead of Jofra Archer - who may not yet be back to full match fitness after his elbow injury, and whose recent workload probably warrants caution at any rate before pitching him back into the fray.
It looked for a time at Newlands as though Pieter Malan was set to script one of the great Test debut performances. While he was at the crease on the final day, utterly serene in the course of his six-hour rearguard, South Africa looked set to put off an improbable escape. But then Sam Curran snagged his outside edge, and his departure for 84 spelt the beginning of the end. Nevertheless, his instant solidity was a boon for South Africa after losing Aiden Markram to a finger injury, and if he can come close to replicating such composure at Port Elizabeth, he'll know that Dean Elgar at the other end won't give his wicket away lightly. Out of adversity, South Africa may just have hit upon a very promising opening partnership.
Du Plessis's form aside, there aren't many areas of particular scrutiny in South Africa's line-up - certainly the form of Rassie van der Dussen and Pieter Malan, the two newest additions to the batting line-up, has helped to assuage many of the awkward questions about Bavuma's continued absence. It is in the bowling ranks where the likeliest change will occur, with Dane Paterson hotly tipped to make his Test debut - although how he'll fit into the side is still somewhat up for debate. The likeliest switch will be for Dwaine Pretorius, to inject a bit of extra bite to a seam attack already featuring Kagiso Rabada and Anrich Nortje. If included, Paterson, who is coloured, will also help make up some of South Africa's transformation target.
South Africa (possible): 1 Dean Elgar, 2 Pieter Malan, 3 Zubayr Hamza, 4 Faf du Plessis (capt), 5 Rassie van der Dussen, 6 Quinton de Kock (wk), 7 Vernon Philander, 8 Keshav Maharaj, 9 Dane Paterson, 10 Kagiso Rabada, 11 Anrich Nortje
England have one enforced change, with Mark Wood likely to edge out Archer and Chris Woakes as Anderson's replacement in the seam attack. Joe Root stopped short of confirming the team on the eve of the match, but England's subsequent nets session seemed to imply that Archer is not yet back to match fitness. He was seen deep in conversation with the team doctor and physio.
England (probable): 1 Dom Sibley, 2 Zak Crawley, 3 Joe Denly, 4 Joe Root (capt), 5 Ben Stokes, 6 Ollie Pope, 7 Jos Buttler (wk), 8 Sam Curran, 9 Dom Bess, 10 Mark Wood, 11 Stuart Broad
Pitch and conditions
It's been hot and dry in the Eastern Cape for months - the bathroom plugs at the local hotels have been confiscated to encourage water saving - and as a consequence, there's the looming prospect of reverse-swing playing a part on what is traditionally one of the slower, lower wickets in the country. The pitch itself looks true, though the abrasive used wicket to the side will be of interest to fielders on both sides - and no doubt to the umpires, as they keep an eye on returns being skimmed into the keeper on the bounce. There was some humidity in the air on match eve, which may encourage traditional new-ball swing, although a westerly wind - which tends to bring more favourable conditions for batting - is forecast over the weekend.
Stats and trivia
This will be England's 500th overseas Test match. Of the previous 499, they have won 149 and lost 182, while their record in South Africa is P83 W32 L20.
England have not played a Test at Port Elizabeth since the opening match of the 2004-05 series - a contest that they won by seven wickets en route to a 2-1 series win. The match was also notable for the debuts of two all-time greats in AB de Villiers and Dale Steyn.
Ben Stokes is within striking distance of reaching 4000 runs in Tests - he is currently 94 away. Should he get there, he would become the seventh player to reach the 4000 runs and 100 wickets milestone after Garry Sobers, Jacques Kallis, Ian Botham, Kapil Dev, Carl Hooper and Daniel Vettori.
Rabada needs five more wickets to become the eighth South African to 200 Test wickets.
"Stokesy being named player of the year was very well deserved. For us, he is a guy we need to try and keep quiet because he is that sort of player that takes the game away from you when he gets in, similar to what Quinton de Kock does for us. Players like that are very dangerous. We know with his bowling as well, big tank and he bowls long overs and tries 150 percent, so it's very well deserved."
Du Plessis reacts to Stokes being named ICC Player of the Year
"You can't worry too often about whether he's going to get through a five-day game. If they've proven themselves to be fit, if they've jumped through every hoop and worked very hard to get back there, you have to give them that opportunity."
Root drops a strong hint that Wood is set for a recall in spite of his chequered injury history