Could Williamson become NZ's best batsman?
Kane Williamson's century in New Zealand's first-test win over the West Indies this week was the sixth of his career and a continuation of recent fine form.
Williamson has now scored 1185 runs at 45.57 since the beginning of the second test against Sri Lanka in late-2012, including four centuries and seven half centuries from 27 innings.
His career average is now 37.12 including six centuries from 32 tests.
This a quality return for a player yet to turn 24.
In fact of the top 10 century-makers in the history of cricket, only Sachin Tendulkar had more centuries at the same age than Williamson currently has.
Two of the players on that list, Steve Waugh and Matthew Hayden, scored no test centuries prior to turning 24, while Rahul Dravid, Brian Lara and Kumar Sangakkara had scored just one.
All of the players on that list went on to play more than 100 tests (149 each on average) and all finished with career averages above 50, despite only two having an average above 50 at age 24.
So to break into that top 10 club Williamson will need to continue the upward trend in his form and play for a long time.
Interestingly he has strikingly similar stats to Martin Crowe, New Zealand's greatest ever test batsman, at the same time in his career.
Both players went into their 32nd tests just a few weeks shy of their 24th birthdays. Williamson, as we know, scored his sixth century while Crowe's sixth came in his 33rd test. Crowe's average was 38.44.
Crowe finished his career with a New Zealand record of 17 test centuries, however, knee injuries impacted the latter part of his career and ultimately forced him into retirement at the age of just 33.
So what is Williamson's range of outcomes for test centuries over his career and how likely is he to break Crowe's Kiwi record? And is there any chance he'll crack the elite club of 30+ centuries?
There are a number of factors which will determine where he ultimately ends up: injury, longevity, form and fixtures.
Form is obviously difficult to accurately predict but what we can say is that it's highly likely Williamson's best years are in still in front of him.
Of the 10 players with more than 5000 runs whose average is closest to Williamson's after 32 tests, all but two saw their career average peak in the second half of their careers. On average they peaked 69 per cent of the way through their playing days.
Williamson's current century output of one in every 5.3 tests is solid, but it will improve if his form does.
Among today's players Matthew Hayden, Kumar Sangakkara and Hashim Amla have the best century per test match output of about one every 3.5 tests.
It's safe to say Williamson will likely score somewhere between this ceiling of 3.5 and his current output of 5.3 tests per century for the remainder of his career.
The next factor to consider is longevity. How long will Williamson continue to play test cricket for? Barring a career-ending injury such as Crowe's, it's difficult to see Williamson playing for anything less than another nine years. On the upside he could play for as many as another 14 years or until age 38.
Thus far Williamson has played little Twenty20 cricket in tournaments like the IPL and that is likely to help prolong his career.
The third factor to consider is fixtures. How many tests New Zealand play per year. New Zealand don't play as much test cricket as many of the stronger nations. For example Australia have played 228 tests in the past 20 years compared to just 165 for New Zealand.
A best case scenario here sees Williamson continuing to play nine tests per year, assuming the recent rate continues and he remains injury-free. In a worst case scenario - New Zealand's tests per year are slashed once the Future Tours Programme expires and Williamson suffers some injuries - he might only feature in six tests per year.
Putting all these factors together what is the range of likely possible outcomes for Williamson?
Barring an injury catastrophe the worst case scenario is another nine years at the top, six tests a year and 5.3 tests per century which would see him notch another 10 centuries in 54 tests and finish on 16 test centuries.
Best case scenario he plays for another 14 years, at nine tests per year and 3.5 tests per century, which would put him in elite company with another 36 centuries from 126 tests, bringing his career total to 42.
Of course a more likely scenario is somewhere in the middle. It's not unreasonable to expect him to play until age 35 (another 11 years), play eight tests per year and score a century every 4.5 tests. In this scenario he finishes with another 19-20 test centuries (25-26 in total).
Whatever happens it is difficult to foresee a scenario in which Williamson does not end his career as New Zealand's greatest ever test run-scorer and century maker.