Which Sri Lanka can South Africa expect?

Meet Sri Lanka, victors of five consecutive Tests, vanquishers of Australia, conquerors of Zimbabwe, scrambling together pace attacks from what seem like the spare parts of older Sri Lankan quicks, and yet, thanks to their lead bowler, rarely failing to leave oppositions in a spin.

Now meet Sri Lanka, losers of six of their last seven away Tests against top-eight opposition, a cacophony of nicks, constantly 50 for 4, masters of the morose end-of-day TV appearance, deliverers of over after over after over of insipid medium-pace, shelling catches like peanuts on the train to Jaffna, sapping the will to watch, driving grown men to tears.

In the first half of the year, Sri Lanka were face-down on the canvas, international critics sounding out the count. Will they become another West Indies? Will Associate sides eclipse them across all formats? Will the global cricket media -say it ain't so - be compelled to ignore Sri Lanka completely, instead of just most of the time? Then they whitewashed Australia at home for the first time in history, and rose like a Lazarus-phoenix-Gandalf-the-white, clutching a sprout of talented young batsmen, even sporting a promising slow bowler who wasn't quite a mystery spinner but was close enough anyway to fit that tired narrative.

So what to expect from Sri Lanka in South Africa? There is a fear that things will play out like they have on recent tours of New Zealand and England. Will balls seek out edges, then pairs of hands in the slips as Vernon Philander needles away on that Vernon Philander length? Will Kagiso Rabada break stumps and shatter confidence en masse?

If there is hope that this batting order will conduct itself creditably, it is because of the recent rise of Kusal Mendis and the auspicious arrival of Dhananjaya de Silva. Mendis is that rare Sri Lanka batsman who comes to international cricket almost readymade, with an all-seasons technique and shots full of conviction, though without much first-class experience, which may be just as well. One of the trending criticisms of Sri Lanka's domestic system is that such has its regression been over the past two decades, it may now be more likely to ruin talented young batsmen than refine them.

De Silva meanwhile, is the stylist in the batting order, which is a more important job than it sounds: ever since Sidath Wettimuny lit up Lord's in 1983, Sri Lanka sides have seemed incomplete without one. He whips balls through the leg side like he is slung in a seaside hammock, and makes footless cover drives feel like other batsmen have been doing it wrong for a century. Though only five Tests into his career, he tamed Mitchell Starc better than any of his teammates, raising hopes that he has a head for handling pace. With de Silva at No. 7, Mendis at No. 4 and Dinesh Chandimal's manic energy at No. 6, Angelo Mathews - for so long Sri Lanka's one-man rescue act - now seems like the middle-order medicine in a sweet shop of island delights.

On the bowling front there are concerns over whether 20 wickets can be prised from South African surfaces, but the outlook may not necessarily be so bleak. On the occasions that Nuwan Pradeep is not picking up his own detached limbs off the pitch in his follow-through, he has made an impressive charge on his bloated bowling average, taking 40 wickets at 32.55 since the beginning of 2015. Dushmantha Chameera is making his way back from a stress fracture but nevertheless has yorkers and bouncers that lend a shock of pace to what can otherwise be a strictly 135kph attack.

Overlooking the scene paternally is Rangana Herath. Perhaps he won't be the force he is at home, but is there a better defender of scores anywhere? This year, he has gobbled up top orders whole in the back end of Tests; his 25 second-innings wickets have come at 14.96. The Port Elizabeth pitch has also traditionally been the slowest of South African surfaces. In Sri Lanka's dream sequence of the first Test they get to the fourth day with some semblance of parity, toss the ball to Herath, and watch him do the rest.

It is a tour of unknowns for Sri Lanka, a chance to break out of endless cycles of transition, to leave the Jayawardene-Sangakkara era unevoked, and to capitalise on six good months. They are world cricket's low-key peddlers of high-volume chaos, so of course things never do quite go so smoothly. Expect at least one tragicomic collapse, a few sessions of fielding japery, maybe a wicket off a no-ball, catches that slip through the cordon like money from the board's travel-and-expenses account.

But for now there is optimistic anticipation from Sri Lanka fans. Another way to say this, though, is that they have been primed for disappointment.