Big picture
Sri Lanka fight at the strangest times. They had several opportunities to dig themselves out of holes against England, at home, on turning tracks specifically prepared to suit them, and yet, what defiances they could muster in that series were insufficient to prevent a whitewash. Somehow, in New Zealand - a country where this group of players had only previously tasted defeat - two batsmen mounted a daylong resistance.
Vitally, in the first away match of six consecutive Tests in the southern hemisphere, Sri Lanka have proved to themselves that their batsmen are not all hopelessly out of their depth. That at least in batting-friendly conditions, they are capable of quelling high-quality seam attacks - the likes of which they will now continuously face until March. Importantly, it wasn't just Kusal Mendis and Angelo Mathews who succeeded. Opener Dimuth Karunaratne and wicketkeeper-batsman Niroshan Dickwella also made runs on day one, when conditions were at their toughest
New Zealand, who have now missed the chance to go to second on the rankings (because only a whitewash against Sri Lanka would have got them there), will perhaps not fret over the Wellington result. Unlike the Basin Reserve surface, the one at Hagley Oval tends to remain receptive to seam bowling right until the final day, particularly if it is very green to begin with, as seems to be the case. Where the Basin track got slower each day, the one at Hagley tends to hold its pace throughout the Test as well. If Sri Lanka had to step up their batting to deal with Tim Southee, Trent Boult and Neil Wagner in Wellington, they will have to climb another rung to face them down in Christchurch.
On top of this, New Zealand's powerful batting order. Jeet Raval generally sees through the worst of the new ball, even if he doesn't quite move on to a substantial score. Kane Williamson seems to begin innings like he's already batting on a hundred, while Tom Latham and Henry Nicholls are also in excellent form. Ross Taylor and Colin de Grandhomme are capable of momentum-shifting knocks, and BJ Watling is often a reliable producer from the lower order. All of which begs the question - have New Zealand ever had it this good?
Sri Lanka have already sprung one surprise in the series. Although they have arrived in Christchurch full of confidence, they will probably need to spring another one in the Boxing Day Test.
Form guide
Sri Lanka DLLLW (completed matches, most recent first)
New Zealand DWLWD
In the spotlight
Neil Wagner has 154 wickets and has bowled in 73 Test innings, but has never collected poorer figures than he did in the second innings at Wellington, when he went wicketless for 100. Beyond the lack of success, Wagner might also be irked at his economy rate of 4.34, in an innings where no other bowler gave away more than 2.5 an over. His short bowling was defanged by a pace-less track, for sure, but there was also the matter of Mendis and Mathews playing him exceedingly well - New Zealand coach Gary Stead later remarked that theirs was "some of the best batting" he had seen against Wagner. For so long "Wagnerline" has worked wonders at home, uprooting stubborn batsmen and sparking collapses after the new-ball swing has disappeared. With Matt Henry forever on the heels of the incumbent seamers, Wagner will want to prove that Wellington was an anomaly.
The Sri Lanka attack, meanwhile, is ostensibly led by the senior Suranga Lakmal, but it is 21-year-old Lahiru Kumara who brings the real energy. He was comfortably the quickest bowler of the first Test, and created more chances on a flat surface than any of his colleagues, claiming 4 for 127 in New Zealand's only innings. He also had an excellent tour of West Indies earlier this year, where he took 17 wickets at less than 20 apiece, so if the Hagley Oval pitch is as seam-friendly as expected, Kumara may have another chance to establish himself as Sri Lanka's primary overseas wicket-taker.
Team news
There is an outside chance Matt Henry will play, but New Zealand will probably stick to the same XI that played in Wellington.
New Zealand (probable): 1 Jeet Raval, 2 Tom Latham, 3 Kane Williamson (capt), 4 Ross Taylor, 5 Henry Nicholls, 6 BJ Watling (wk), 7 Colin de Grandhomme, 8 Tim Southee, 9 Neil Wagner, 10 Ajaz Patel, 11 Trent Boult
As Kasun Rajitha went wicketless in Wellington, Sri Lanka may be tempted to swap in Dushmantha Chameera, who averages 24.00 in New Zealand, but has not played a Test since late 2016, largely due to injury. Otherwise, it will probably be the same side.
Sri Lanka (possible): 1 Dimuth Karunaratne, 2 Danushka Gunathilaka , 3 Dhananjaya de Silva, 4 Kusal Mendis, 5 Dinesh Chandimal (capt), 6 Angelo Mathews, 7 Niroshan Dickwella (wk), 8 Dilruwan Perera, 9 Suranga Lakmal, 10 Dushmantha Chameera, 11 Lahiru Kumara
Pitch and conditions
A green, seaming track is expected, but showers may interrupt play on the first two days. Clouds overhead may mean that the ball swings more. Sri Lanka will be especially unimpressed to note that the temperature is unlikely to make it out of the teens until days three and four, with wind-chill likely to make it seem even colder.
Stats and trivia
Neil Wagner's bowling average against Sri Lanka is 38.92 and his economy rate is 3.78 - both his worst against any team he has played. Wagner has only bowled to Sri Lanka across four Tests in New Zealand.
Lahiru Kumara's bowling average this year is 26.66, despite having played two of his five Tests on flat pitches, in Chittagong and Wellington.
With one Test to go, two Sri Lanka batsmen are among the top five run-scorers for the year. Kusal Mendis is third, with 941 runs at 47.05 (he has a chance of being the second after Virat Kohli to make 1000 runs in the year). Dimuth Karunaratne is fifth, with 736 runs at 52.57.
Among batsmen with more than 400 runs this year, Kane Williamson (66.77) and Henry Nicholls (61.87) comfortably have the best averages.
Quotes
"We weren't surprised by the way Sri Lanka played in Wellington. They are a very good side. They showed a lot of character and grit in that second innings. We're preparing for them to be exactly the same in this Test."
New Zealand batting coach Craig McMillan
"We've got some confidence. Angelo is batting really well and knows how to play in these conditions. Kusal has got runs as well. I'm sure Dimuth and the others will chip in as well."
Sri Lanka wicketkeeper-batsman Niroshan Dickwella