Indias big win over England in Chennai in the second Test not only helped them level the series.
It has also put them back in contention for a place in the ICC Test Championship Final, which will be played for the first time on English soil this June, probably at Lords.
New Zealand have already booked their place in the final and the one remaining spot is between India, Australia ,and England.
Australia can do no more. They have 69.2% from the matches they have played, and have no further chance of improving on that because their tour to South Africa has been cancelled. Australian medical experts advised that the risk to players, their support staff, and their families, was too great, given the local South African strain of the coronavirus.
Conversely though, their results cannot get any worse either, so not playing has its advantages.
England had briefly moved into second place in the rankings after their first test victory in Chennai. However, their second test defeat saw them tumble from second to fourth and with a rating of 67% they must now be regarded as the outsiders.
So delicately balanced though is the situation, that India need at least a win and a draw from the last two tests in Ahmedabad to make sure of their final spot.
Anything other than that and, depending on results, it could still let in Australia or conceivably, England.
When the World Test series was originally conceived, the intention of the ICC was to use a points basis to determine the final standings, with so many points awarded for a win or draw, depending on the matches in a series.
However, last December, they decided to change this toa percentage basis as fairer, recognising that the global pandemic meant that not all the test playing nations were able to play all their scheduled matches as originally envisaged.