Cricket: Black Caps captain Kane Williamson usurped as top test batsman by former Australian skipper Steve Smith

Black Caps skipper Kane Williamson has been dethroned as international cricket's best batsman.

One day out from the inaugural World Test Championship final against India, Williamson is preparing for his return to the crease after missing the second test against England due to an irritated left elbow.

However, his exclusion from the eight-wicket win over England has proven costly among his own triumphs, with former Australian captain and perennial run-scorer Steve Smith overtaking Williamson and returning to the top of the International Cricket Council's (ICC) test batting rankings.

Williamson's fallen to 886 ranking points, now behind Smith who is on 891. The New Zealand captain scored a mere 14 runs in the first test against England.

The change in rankings does contrast how the past 12 months have eventuated for the two batsmen. Williamson's averaged an incredible 108.8 runs across his last six innings, highlighted by two double centuries and three singles in total.

However, Smith has had a quiet year in comparison with an average of just 39.12 across eight innings batted, all during Australia's home series against India. He hasn't played a test match since January.

Smith's highlights came in the form of 131 and 81 in the third Indian test in Sydney, before scoring another half-century in the fourth match in Brisbane.

Black Caps captain Kane Williamson is no longer test cricket's best batsman in the world. Photo / Photosport

According to the ICC, the former Australian skipper has been at the top of the batting rankings for 167 tests, which only sits behind Gary Sobers and Viv Richards who were top for 189 and 179 tests respectively.

India skipper Virat Kohli moved up to fourth on the list, ahead of England captain Joe Root who himself struggled in the recent two-test series against New Zealand, hitting 42, 40, 4 and 11 across four innings.

Root has still been England's most productive scorer in the past year, with a total of 1115 runs at an average of 50.68.

Meanwhile, Williamson's teammate and fellow batsman Henry Nicholls has provided an update on his leader's health ahead of the inaugural final starting on Friday night (New Zealand time) in Southampton.

Nicholls said Williamson is trucking along well.

"He had a good hit out today – good long hit in the nets," Nicholls said.

"Obviously he's a skipper and the way he bats is tremendous so it was a shame to miss him in the last test and I certainly know he's doing everything he can to get right for the final."