How good have India been in Tests under Kohli?

Under Virat Kohli, India average 26.33 with the ball in Test cricket. Among all teams led by one captain in 30 or more Tests, only four have ever done better: Viv Richards' West Indies, Hansie Cronje's South Africa, and the England sides led by Mike Brearley and Peter May.

By this crude metric, Kohli has led better bowling attacks than Ian Chappell, Clive Lloyd, Steve Waugh or Ricky Ponting did. This is why Kohli, upon becoming India's most successful captain, at the conclusion of their recent tour of the West Indies, turned the attention away from himself and towards his bowlers when asked about his achievement.

"Captaincy is just a 'c' in front of your name, honestly," he told Ian Bishop at the presentation ceremony at Sabina Park. "It's the collective effort that matters. It's a byproduct of this quality team that we have here. If we didn't have the bowlers that we have, I don't think the results would have been possible."

The results have been remarkable, and unprecedented in an Indian context. Kohli has won 28 of his 48 Tests as captain, achieving a win percentage (58.33) that is behind only Waugh and Ponting among the 50 captains who have led their teams in 30 or more Tests. MS Dhoni, the next Indian on that list, is in 20th place, at 45.00%, and Sourav Ganguly is 22nd, at 42.86%.

That Kohli's side has been so far ahead of previous India teams in terms of results is almost entirely down to bowling strength. With the bat, India average 37.48 under Kohli. That number is in the same ballpark as the batting averages of the teams led by five of the other six captains to lead India 30 or more times - Dhoni (37.00), Ganguly (38.74), Mohammad Azharuddin (36.51), Kapil Dev (36.13) and Sunil Gavaskar (37.90). Only MAK Pataudi (28.19) led a significantly weaker batting team.

But India's captains before Kohli had far less incisive bowling attacks at their disposal, their averages ranging from 32.50 under Pataudi to 36.38 under Gavaskar.

If we plot these averages on a graph, most of India's captains occupy a tight cluster of impressive batting averages and middling bowling averages. Kohli sits apart from them, in the company of some of history's most successful Test captains.

In the context of the era they have played in, where pitches have tended to challenge batsmen considerably, the batting numbers of Kohli's team shouldn't be underestimated. In terms of the difference between batting and bowling averages, only one team, Waugh's Australia, has done better than Kohli's India, among the 50 teams that have been led by one captain at least 30 times.

However good a batting team is, though, it is bowlers who win Test matches, and Kohli owes much of his success to the good fortune of being able to lead India's first great all-conditions bowling attack. This has afforded him a bigger and better toolkit than the ones his predecessors worked with.

Take the job of captaining Ishant Sharma. Under Dhoni, Ishant was an earnest but limited workhorse, with a flawed wrist position that made him prone to being erratic and restricted the range of things he could do with the ball. It was out of sheer necessity that deep point routinely made an appearance when Dhoni captained Ishant. Under Kohli - and perhaps more pertinently, India's bowling coach Bharat Arun - Ishant has improved to an almost unrecognisable level. While he has always had the ability to hit the deck and trouble batsmen with bounce, he is now also able to swing the ball consistently. Bowling from around the wicket and swerving the ball against that angle, he is now one of the world's most dangerous bowlers against left-hand batsmen. If the ball is old and nothing is happening, Kohli can still rely on him to build pressure with his accuracy.

In earlier eras, bowlers as good as Ishant or R Ashwin - who went through a similar transformation himself - would be indispensable to India. Kohli, however, has so sizeable a pool of resources that he can leave Ishant out when he plays only two fast bowlers, as he did in Sydney in January, or leave Ashwin out when he plays just one spinner, as he did in the West Indies. Umesh Yadav, who took ten wickets in his most recent home Test, wasn't even in the original squad for the upcoming Tests against South Africa. Seven of the eight bowlers who have taken 30 or more wickets under Kohli have averages of less than 30. Ten bowlers took 30 or more wickets under Dhoni, and only one of them averaged less than 30.

Kohli's biggest challenge as a captain, therefore, has been that of choosing from all his options. There has seldom been an obvious best XI in his time as captain, and if there was an early pattern in his choices, it was that he usually erred on the side of the more aggressive option, and risked defeat in the pursuit of wins.

He demanded spin-friendly pitches during his first home series as captain, against a South Africa team that had lost only two Test series in India in two decades, and said his batsmen were prepared to suffer a drop in their batting averages if the bowlers were able to take 20 wickets more often. He often played five bowlers - or four specialists and an allrounder - in even the most challenging batting conditions. When there was a choice to be made between trying to play for safety and going after an outlandish target, his team chose the latter, and potential draws in Adelaide and at The Oval turned into thrilling defeats.

But that pattern seems to be changing. Since the last Test of the 2018 England tour, India have left out the allrounder Hardik Pandya, and reverted to having the cushion of a sixth batsman. Even the choice of Ravindra Jadeja over Ashwin in the West Indies - at No. 8 - was partially influenced by their recent form with the bat. Last year's defeat in Perth - where they played four fast bowlers, all of them No. 11s or at least No. 10s - seems to have instilled in Kohli and India's coaching staff the recognition of a need for more batting depth.

This shift in philosophy has coincided with the start of the World Test Championship, where a more measured approach could come in handy, with useful points to be earned for drawing Test matches. Draws are no longer as commonplace as they used to be, but it is one area where Kohli's India still have a way to go before matching some of the great teams of the past. While Chappell's Australia or the West Indies teams led by Lloyd and Richards didn't win as high a percentage of their Test matches as Kohli's India have done, they were a little harder to beat, as their win-loss ratios would suggest.

India, over the course of their first full away cycle under Kohli, were a team that pushed strong teams hard in their own backyards but lost more often than they won. With their World Test Championship cycle set to include home series against South Africa and England and tours of New Zealand and Australia, can they take the next step in their evolution?