Alastair Cook has faced 8273 balls of spin in his Test career. He has been bowled out by three of those deliveries. The first was bowled by Pragyan Ojha, at the end of Cook's series-shifting 176 in Ahmedabad four years ago. It was the 4944th ball of spin the England opener had faced in Tests, meaning he had faced the equivalent of more than nine complete Test days of spin before a tweaker hit his stumps, at which point his career tally against spin was 2252 runs for 33 dismissals, at an average of 68.
Since then, he has been bowled out by Nathan Lyon, at The Oval in 2015 (the only one of the 5516 balls of right-arm spin to have shifted Cook's spinnimpregnabails); and by Shakib al Hasan in Chittagong last month.
Ben Duckett, by the most alarm-clanging of comparisons, has faced 172 balls of spin in his Test career. He has also had his timbers rattled by three of them (and been caught off four of the others). Duckett has been bowled once every 9.3 overs off Test tweak; Cook once every 459.4 overs. It appears that only one of them will be playing in the third Test, in Mohali.
Clearly, not being bowled out is only one facet of batsmanship, and I am comparing a flamboyant attacker with statistically one of the toughest players to bowl out in Test history (although Cook's stumps have been far more regularly clonked in the past three years - 15 times in 39 Tests since Adelaide 2013-14, when Mitchell Johnson bowled him with a masterpiece of high-speed unplayability that would have bowled out a brick wall; 12 times in 98 Tests prior to that).
Nevertheless, Duckett's spin-stump-vulnerability numbers are striking. And to a large extent, unsurprising. Few England debutants can have had such a difficult introduction to Test cricket since fresh batting meat was fed to the rampant West Indian pace lions in the 1980s and early 1990s.
Duckett, on debut, faced 12 balls of Mehedi Hasan's offspin before he first faced a seamer. He then faced two overs of Shafiul, and one of Kamrul Islam Rabbi. Since when, he has faced nothing but spin - 160 consecutive balls of tweak, twirl and torture.
By comparison, Duckett's three predecessors as Test debutants in the opening batting slot - Sam Robson, Adam Lyth and Alex Hales, who played an entire English summer each (plus a series in South Africa in Hales' case) - between them have faced 2065 balls of pace and 526 balls of spin.
The 20% of spin deliveries faced by Robson, Lyth and Hales reflects almost exactly the proportion of spin bowling in the last summer's County Championship Division Two, where Duckett played with such success and panache. Spinners bowled 19.5% of the overs, taking 14.3% of the bowlers' wickets. The figures for all first-class cricket in England over the past two years are similar (23.9% of the overs and 20.1% of the wickets). Duckett found himself stepping up from the lower tier of county cricket into Test cricket in Asia - where, this decade, 58.5% of the overs and 60.3% of the wickets have belonged to spinners. Robson, Lyth and Hales struggled in an examination for which they had spent their careers preparing. Duckett has almost been trying to learn a new sport.
Hardened Test veterans have struggled in India recently - Hashim Amla managed just 118 runs in seven innings a year ago in India, having averaged 93, with seven centuries, in his previous 11 Tests in Asia. Faf du Plessis began the same series averaging over 50 after 22 Tests. He scored 1 for 3 in the first 13 balls he faced in the series, and finished with 60 runs in four Tests. Nor does an initial failure necessarily presage lifelong struggles. Mike Gatting scored 109 runs in his first seven Tests in Asia but went on to score 575 runs at 95 on England's 1984-85 tour.
Haseeb Hameed, with a tighter, defensive-oriented technique, and without having his game pre-scrambled by the difficult wickets in Bangladesh, has prospered in India, and looks set for a long career as a delightfully stylish old-school Dravidian grinder for England. But at least he had the advantage, in three of his four innings, of facing a few overs of pace before the tweakers came on (he has faced, in his four innings, 25, 5, 29 and 18 balls of pace before facing a spinner). The same applied to Cook in his famous debut in 2005-06, when he made 60 and 104 not out against Kumble and peak Harbhajan.
Roland Butcher, Andy Lloyd, Paul Terry, David Smith, Wilf Slack, Tim Curtis, Rob Bailey and Matthew Maynard, who all made their debuts against the 1980s West Indians and were swiftly consigned to the Test match scrapheap, might have dreamed of facing an attack that gave them 90% spin. Graeme Hick and Mark Ramprakash, who began against Ambrose, Marshall, Walsh and Patterson in 1991, would no doubt have bitten their own arms off for the prospect of that quiver-inducing quartet bowling only 10% of the overs in their debut series.
In terms of the chasm that these newcomers of different generations have been asked to straddle, Duckett's was just as wide. Nothing in county cricket could have prepared him, and it is to be hoped that the experience will not adversely affect his game or his prospects.
He has failed, and, with the exception of what should have been a match-turning half-century in Dhaka, failed badly. What has been learned about him in his four Tests? Not much of long-term relevance, I think. He has shown talent, strokeplay, cojones, exploitable frailties that could be rectified (a tough assignment in the zero days of cricket between the Tests on this tour). And an absolute impregnability against pace.
Or, at least, an absolute impregnability against the 18 balls of pace that he has faced. How many top-order batsman have remained undismissed by pace bowlers in their first four Tests? Very few, I would guess. Perhaps none. As starts to a top-order Test batting career go, Duckett's winter has been roughly equivalent to passing your driving Test, then being plonked into Apollo 11 and told to pilot it to the moon and back. If I may exaggerate slightly.
"Duckett has shown talent, strokeplay, cojones, exploitable frailties that could be rectified. And an absolute impregnability against pace"
England's selectors owe him the chance to test his talents in the alternative cricketing universe of non-Asian Test cricket; English cricket owes the Ducketts of the future the chance to learn more of the skills they will need in the unforgiving, judgemental Test arena, before they are shunted into that arena with a cursory "Don't worry, it'll all be over by Christmas."
● England, of course, are not the only Test team making changes. Australia introduced three debutants in the third Test, in Adelaide, after jettisoning the two debutants who had been baggy-greened for the first time in Hobart, making this the first series since the 1981 Ashes in which Australia have given Test debuts to five players. England, by selectorial contrast, did so seven times from 1984 and 1997, before central contracts came in and ended everyone's fun, bringing a sad close to the days when county batsmen's hearts would flutter in anticipation after edging a cut for four, hoping that those runs might be enough to catapult them into the international arena.
Adelaide is only the third Test in the past 30 years in which Australia have given debuts to three players in the same match - England have done so eight times in that period, India and Pakistan six each - and only the fourth time since Bodyline in 1932-33 that they have done so during a series (rather than in the first Test).
The most recent of these four was when they brought in four brand-new players as part of six changes for the decisive fifth and final Packer-era Test against India in 1977-78, following two thumping defeats. Rick Darling, Graeme Wood, Bruce Yardley and Ian Callen were the ninth, tenth, 11th and 12th debutants for Australia in that series, and helped their nation win a high-scoring classic.
This is only the fifth time since the 1880s that Australia have selected two or more players for their first caps in consecutive Tests in the same series - they did so in that 1977-78 series against India, in the 1972 and 1928-29 Ashes, and against South Africa in 1931-32.
And, to conclude the Australupheaval stats, this is the first time a team has deliberately picked three debutant specialist batsmen in the same Test since Pakistan did so against New Zealand, fifteen-and-a-half years ago, in March 2001. Those men were Faisal Iqbal, Imran Farhat, and a seasoned player approaching 27, who, in those days of youthful Pakistan batsmanship, might have thought his international prospects had already disappeared, by the name of Misbah-ul-Haq. (I exclude West Indies v Bangladesh in 2009 and Zimbabwe v Sri Lanka in 2004, when disputes with governing bodies led to selectorial mayhem.)
(In fact, excluding those matches, nations' maiden Tests, South Africa's first two games after readmission in 1992, and a couple of instances in the Packer era, Adelaide provides only the third instance of three debutant batsmen being picked in a Test since 1970; other than the Misbah debut, the other occasion was when Sri Lanka, in only their sixth Test, overhauled their team with seven new caps for the first Test in New Zealand in March 1983.)