Bridgetown - Australia drew on their middle-order batting strength to crush Sri Lanka by 81 runs in today's Twenty20 world championship Super Eight cricket match.

The win virtually assured Australia of a place in the semifinals, although Michael Clarke's side also face an important Super Eight match against West Indies in St Lucia on Wednesday (NZT).

Man-of-the-match Cameron White smashed a career-best 85 not out as Australia recovered from 67 for five to score 168 for five.

Sri Lanka were bowled out for 87 in 16.2 overs with Mitchell Johnson taking three for 15.

For the fourth time in four matches in the tournament, Australia's pace attack of Dirk Nannes and Shaun Tait made early breakthroughs.

The tournament's leading runscorer Mahela Jayawardene, was out for nine hooking to Nannes as was Kumar Sangakkara to the 149km/h Tait, for two.

Nannes trapped 40-year-old opener Sanath Jayasuriya lbw for five and White took a diving catch to remove Tillakaratne Dilshan for 20.

Johnston took two wickets in his first over, also dismissing Angelo Mathews as Sri Lanka reached 49 for five.

Australia's batting heroics mirrored their effort in the group A match against Bangladesh on Wednesday, rebounding from 65 for six to a total of 141 for seven including Mike Hussey's 47 not out.

This time Hussey played the support role with an unbeaten 39 from 26 balls.

The aggressive White blasted six fours and six sixes from 49 deliveries.

Mathews gave Sri Lanka a great start by removing Shane Watson and Brad Haddin in the first and third overs of the innings.

Next over spinner Suraj Randiv claimed the wickets of David Warner and David Hussey in successive balls.

Clarke, on 14, added to his side's problems with his dismissal trying to cut a ball from Randiv off his stumps at 67 for five.

In just his second T20 international, Randiv took three for 20 after coming into the side for spin wizard Muttiah Muralitharan who has quit the tournament with a groin strain.

- AAP