Steve Smith's century in the Boxing Day Test has catapulted him back to the top of the ICC's Test batting rankings (see full rankings tables below).

The 26-year-old followed up his polished 134 in the first innings against the West Indies with an inventive 70 not out in the second dig to see him take top spot back from New Zealand's Kane Williamson.

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Meanwhile, the long reign of South Africa's Dale Steyn as the No.1 ranked bowler is over, with Indian spinner Ravi Ashwin now holding that mantle.

Smith's performance in Melbourne saw him jump ahead of Williamson, South Africa's AB de Villiers and England's Joe Root.

Such is the log-jam at the top of the batting rankings, Smith, De Villiers, Root and David Warner all had the chance to overtake Williamson and finish the year as No.1.

While Williamson was busy in the ODI series against Sri Lanka, Root scored 24 and 73, de Villiers made 49 and 37 and Warner chipped in with 23 and 17. But it wasn't enough to top Smith, who finishes the year 10 points ahead of Williamson, on 899.

He is the third Australian batsman in the past decade after Ricky Ponting (2005 and 2006) and Michael Clarke (2012) to finish the year in the No.1 position.

Adam Voges also reached a career-high ranking of 11 following his century at the MCG, while Usman Khawaja's third consecutive Test ton has moved him up 11 places to 39th. Joe Burns moved up 10 places to No.51 following his first-innings ton against the Windies.

The other big winners in the latest rankings were Proteas opener Dean Elgar (up 12 spots to 28) and England duo Jonny Bairstow (up 13 to 43) and James Taylor (up 46 to 61).

Ashwin, meanwhile, became the first Indian since Bishen Bedi in 1973 to finish the year as the world's No.1 ranked bowler.

The off-spinner finished the year with 62 wickets in nine Tests, ensuring he took over from Steyn, whose year has been ruined by injury.

The Proteas speedster took four wickets in the first innings of the first Test against England, but a shoulder injury restricted him to 3.5 overs in the second innings.

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