Do you remember Yasir Shah's ten-for at Lord's in 2016? Of course you do. You're reading an article about Pakistan on the afternoon of a dead Test, an article about a Pakistan player who isn't even playing. One imagines you are enough of a follower to remember that spellbinding summer in England.

There isn't much time to reminisce, though, because the subject of discussion here isn't Yasir at his most lively. The point is that Yasir has, throughout his career, been surprisingly ordinary in Test cricket in South Africa, Australia, New Zealand and England.

Perhaps this isn't quite fair, and we are cheating slightly. There isn't all that much evidence he is as astonishingly ineffective in England as in those other three countries - though anyone who watched him at Manchester and Birmingham in 2016 might beg to differ. He was unlucky to miss the two Tests in England last summer, depriving us of a clearer gauge of where he stood in the country of the game's origin. So for now, let's do what the Rugby World Cup tends to do, and set up camp in the Southern Hemisphere.

For all that you might rave and rant at Pakistan's selectors this series, it is hard to take issue with the call they made to drop the legspinner for the Wanderers Test. A statement from the PCB later revealed that Yasir was at a Johannesburg hospital undergoing scans on his knee. But, while the nature of his injury was unclear, it is understood he was not in line to play in any case.

Yasir might be the world's best spinner according to the rankings, but in six Tests in South Africa, Australia and New Zealand, he has taken just nine wickets at a staggering 95.11 per dismissal. Much of the blame for these incriminating numbers is owed to the three-Test series in Australia in 2016-17, where he bowled 148.1 of the 194.2 careers overs he has sent down in these three countries, but in the small sample size available for South Africa, there's little to make you think his performances shape up any differently. At Centurion and Cape Town, he managed a solitary wicket while conceding 123 runs, with an economy of just under four runs per over.

And that has been the other issue; many bowlers, especially spinners, go through spells of struggling for wickets. Many of them make up for it by holding up one end, building pressure while a more potent bowler makes their mark from the other end. In the Southern Hemisphere, though, Yasir's economy rate soars to 4.40, as opposed to 3.09 in his career, meaning he is bleeding runs without threatening to make a breakthrough. That is a damaging combination, but to his own team rather than the opposition.

The most unfair thing you could do to a spinner is damn him by his statistics in the least-hospitable parts of the world for his art, but for the world's leading leggie, a man who just recently became the quickest-ever bowler to 200 Test wickets, these are alarming numbers. R Ashwin, who has played ten Tests south of the equator, does see his average suffer too, going to 47.67 against a career average of 25.43. But the drop isn't as drastic and, moreover, his economy rate takes only the slightest hit (2.97 against 2.84). Ravindra Jadeja is another good example of a player who makes up for lack of wickets in the South with parsimony. While his average drops from a career 23.68 to 38.18 in five matches, his economy rate only rises to 2.54 from 2.37.

Those two may be finger spinners, who can expect to containment to be more of a focus than a leggie like Yasir, but when you are not taking wickets, tolerating such a massive jump in the economy rate becomes that little bit harder.

In short, across a similar number of Test as some of his leading contemporaries from the subcontinent, Yasir has failed to raise his game to the level Pakistan have required it. One mitigating factor might be him being the victim of less-than-ideal planning. Just as recently as the first Test in South Africa, Mickey Arthur admitted playing Yasir was a mistake, with the bowler used for under 12 overs all match on a pitch really not meant for any spinner.

Of specialist spinners to have played five Tests in Australia, South Africa and New Zealand since 2010, none has an average as high as Yasir's

Next match, in Cape Town, South Africa opted for an all-pace attack while Pakistan still had Yasir plugging away on a relatively flat day-two wicket. He conceded 79 in 21 overs and went wicketless, and with the game finished within the first hour of day four, it was another Test that was never going to be good for his numbers.

By contrast, Ashwin has only played ten of India's 19 Tests in Australia, South Africa and New Zealand since his debut in 2011, while Jadeja has been involved in five. That suggests the Indian spin duo have only been called upon when the pitch or situation was more likely to be conducive towards their talents, in turn allowing them better numbers (Yasir, meanwhile, played six of seven such Tests for Pakistan up to Johannesburg). But since April 2010, of all specialist spinners to have played at least five Tests in those three countries, none has an average nearly as high as Yasir's, or close to as generous an economy rate.

For Pakistan, that meant Shadab Khan, still very much unproven as a bowler at this level but a "proper allrounder", according to Mickey Arthur, was always going to be a more attractive option once fit. With Shadab slotting in at No. 7, Faheem Ashraf could also be ushered in without any fear of extending the tail.

So Yasir's dropping may not have too much to do with his inability with the bat. When it comes to the Southern Hemisphere, it is the troubles he has with the ball that are chiefly responsible for him sitting out at Wanderers.

Danyal Rasool is a sub-editor at ESPNcricinfo. @Danny61000