Australia's pace bowlers sent Sri Lanka crashing out of the World Twenty20 championships at Newlands Thursday.
Sri Lanka tumbled to 101 all out in 19.3 overs after being sent in.
Australian opening batsmen Adam Gilchrist and Matthew Hayden needed only 10.2 overs to take their side racing to a ten-wicket win in a Super Eights match that was effectively a knock-out encounter.
Australia made sure of joining Pakistan in the semi-finals while Sri Lanka were eliminated.
Pakistan were due to play Bangladesh in the second match of a double-header. If Pakistan won they would top the group but a defeat would enable Australia to go ahead on net run rate.
The match was effectively decided in the first few overs after Gilchrist, Australia's stand-in captain, won the toss.
Stuart Clark took four for 20, the best figures by an Australian bowler in Twenty20 internationals.
Clark built on early breakthroughs by Brett Lee and Nathan Bracken, who took advantage of early life in the pitch. The first three wickets fell for 11 runs in the first three overs.
Clark took over as Sri Lanka crashed to 43 for seven before Jehan Mubarak and Chaminda Vaas put on 40 for the eighth wicket.
Mubarak made top score of 28 before lofting a catch to extra cover off all-rounder Shane Watson, playing in his first match of the tournament.
But Watson had to leave the field after bowling two balls of his fourth over, clutching the left hamstring that had kept him out of action.
Watson replaced Australian captain Ricky Ponting, who was ruled out of the rest of the tournament because of a hamstring injury suffered during his team's defeat against Pakistan in Johannesburg Tuesday.
Gilchrist and Hayden snuffed out any chance of Sri Lanka fighting their way back into the match with aggressive batting.
Hayden hit his third half-century of the tournament, making 58 not out off 38 balls with seven fours and two sixes.
Gilchrist was unbeaten on 31 off 25 balls.