He's weird, he's wonderful, he's Wagner

On the last morning of a Test Sri Lanka are trying to save in Dunedin, Angelo Mathews is preparing to face his 61st delivery. At this moment in time - December of 2015 - there are few better batters for this situation.

Since the start of 2013, Mathews has averaged 63.11, hitting most of his runs from No. 6, but right now he is in the kind of fight he has never been in before.

New Zealand have a left-armer surging in with rage in his eyes. With Tim Southee and Trent Boult also in the attack, Sri Lanka's pre-match planning had probably glossed over this bowler. He is not particularly fast, not especially tall, and 16 Tests in, his average is in the mid 30s.

He also only has a heavily used ball in his hand, so however much rage his eyes contain, he is less fearsome quick striking fear into batters, more angry dad charging across the garden to deal with the eight-year-old who's shoved his little brother into a bush.

But angry dad has been bowling bouncer after bouncer after bouncer. And honestly, it's starting to grate. Out of 15 balls, 13 have been at the body. Mathews has swayed out of the way sometimes, got on top of the bounce and deadbatted onto the pitch, ducked when required. The previous deliveries he shuffled to off and let the rising ball pass by his ribs on the leg side.

What happens next is so strange you wonder if space-time has been warped.

Angry dad comes from wide of the crease, the leg-side field stilll packed.

Mathews is expecting another one at his ribs, but the bowler has gone at the stumps this time.

And, oh, Mathews has offered no shot. He has only plonked his pad in the way, like he might against a spinner pitching balls outside leg stump.

The ball flicks the pad, crashes into the wicket.

The bowler wheels away in celebration.

He leaves you trying to reconcile everything you've seen before in cricket with what has just transpired: a top-tier batter has been bowled trying to pad away a quick.

This is not a bowler who has beaten Mathews with pace or skilll.

He's found a way to short-circuit his brain.

Deep below the ocean's surface, beneath the billions-strong sardine shoals, below the technicolour rampage that are coral-reef systems, down past the deepest great white sharks and killer whales, are the lowest reaches, where light fails to fall and food is vanishingly scarce.

Although these depths seem utterly inhospitable, life can still exist here. But you've gotta get weird.

You could be an anglerfish with a bioluminescent lure on the end of a spike sticking out of your forehead, plus a flexible jaw full of backward-facing nightmare teeth. You could be a barreleye fish, with a transparent head, and internal eyeballs that look directly upwards as they scan for what little prey swims by. Or maybe a stoplight loosejaw with red and green suborbital photophores (lights, basically) that help you illuminate your surrounds in light frequencies your prey cannot see.

In an environment where few opportunities come your way, the only way to thrive is to become a crazy ultra-specialist.

Neil Wagner came up in a South Africa where Dale Steyn was en route to becoming one of the greatest ever, where Morne Morkel pelted down steepling bouncers like asteroids from the sky, where Vernon Philander was preparing to bag up entire batting orders with immaculate seam presentation, and in which the likes of Kyle Abbott, Wayne Parnell, Marchant de Lange or Duanne Olivier were scrapping for places in the Test side.

So aged 22, Wagner moved to the lowest reaches of the cricketing world - Dunedin - seeking a less crowded field. But by the time he'd qualified to play for New Zealand, he found that even here there was a fast-bowling explosion. Boult and Southee had cornered the big-swinging, new-ball bowling market. In the wings were Matt Henry and Doug Bracewell, with allrounders Corey Anderson and James Neesham also making their charges.

Not especially fast, not especially tall, not a massive swing or seam bowler,, what's a guy to do?

Down here, you've gotta get weird.

Weird like with your lengths. Other bowlers aim for top of off, Wagner begins to aim for the batter's rib cage. Other bowlers bowl wicket to wicket in New Zealand, looking for lateral movement off the air or off the pitch. Wagner frequently bowls from so ridiculously wide, he's probably closer to his house than the set of stumps. And if Southee and Boult will always get the new ball, Wagner wills himself to become a menace with the old one.

That Mathews wicket is one of Wagner's first forays into the realm of short-circuiting the brains of international batters, but short-circuiting increasingly becomes his business, because in a sense he is short-circuiting Test bowling in general.

The next several years are intense. Wagner whanging the old ball relentlessly into batters' armpits with a leg gully, short leg, and several other fielders square on the leg side. His captains unable to convince him to end his spells, which frequently go longer than ten overs, especially when New Zealand are chasing wins.

And batters who have played tens of thousands of deliveries, but never these particular lines and lengths, swatting, hopping, turned inside-out into living punctuation marks, rubbing ribs, biceps, and shoulders when they are hit, hoping desperately that that last over was Wagner's last for a while, but holy crap, here he is bounding in again. The whole thing is underpinned by Wagner's gruelling personal fitness routine, and a heart as big as a house.

The dismissals are all caught behind, or miscued to square leg, or fended away off the shoulder of the bat to gully. Because the three sticks sticking out of the ground don't matter. The batter's resolve, his patience, his will to stay in the fight - this is what Wagner pits himself against.

The results are staggering, for a bowler who has essentially reverse-engineered his method to find a place in Test cricket. Forty-one wickets at 21.04 in 2016, 36 wickets at 25.47 in 2017, and then an outstanding 2019, when Wagner takes 43 at 17.81, and ends the year with two five-wicket hauls against England at home, followed by an excellent series in Australia, where he dismisses Steve Smith four times out of five.

Among New Zealand bowlers with more than 100 wickets, Wagner's strike rate is second only to that of Richard Hadlee. Wagner hasn't just carved out his own role, he has embraced adaptations like no bowler has before, and willed himself to thrive in his niche.

It's no real surprise that he had to have the ball prised from his hand. Wagner is 37 now, and his work has been punishingly physical. The retirement was brought on not by a desire to walk out while on top but because his team let him know he would not be selected - a bowler who has strived desperately to be useful, whose relentlessness is at his very core, forced to confront the notion he was no longer needed.

There is no doubting how much each of his Tests meant to him, and understandably, there were tears at his final press conference, and talk of his extraordinary determination. But there was immense joy to his work too. He'd throw his angry-dad glares, gesticulate at batters he troubled, then in between overs, jump across the fence at Hagley Oval or the Basin Reserve and smile the biggest ray-of-sunshine smile in selfies with little children.

And he has changed Test cricket slightly, though he was never really going to recast it in his own image. When pitches are flat and teams are chasing those second-innings wickets, seamers tend to be quicker now to change their angles of attack and go at the body - Sri Lanka's Asitha Fernando being one example. Even Boult and Southee, to whom the fuller lengths come much more naturally, have embraced sustained bouncer barrages. No one quite bowls the epic spells Wagner did, of course.

The extent to which Wagner specialised is evident in his having bowled in only 82 T20 innings (all domestic), compared to his 122 in Tests. This is, by any ancient or modern measure, a career like no other. Other bowlers have had bursts of success this way. No one has made it stretch to a 260-Test wicket career.

In the great halls of fast bowling, Wagner may be little thought of. He is not the scariest or most charismatic of the species - not the orca or the great white. But in so doggedly charting his own singular path, he has given Test cricket a thing of no little freakish wonder.