Australia 179 for 5 (Finch 63, McCarthy 3-29) beat Ireland 137 (Tucker 71*, Maxwell 2-14) by 42 runs
Brisbane: Australia beat Ireland by 42 runs to boost their hopes of reaching the Men's T20 World Cup semi-finals, and also hurt England's last four chances in the process.
After racking up 179-5 in Brisbane - captain Aaron Finch returning to form with 63 from 44 balls - they bowled Ireland out for 137 in 18.1 overs.
The result effectively ends Ireland's challenge but is also damaging for England, who play their penultimate game of the group against New Zealand on Tuesday.
Australia's net run-rate, which will split the teams if both England and Australia win their remaining games, has closed up on England's.
Australia play Afghanistan in their final group game - a match they will expect to win convincingly - while England play Asia Cup champions Sri Lanka after their assignment with New Zealand.
But Australia's win on Monday was perhaps not as convincing as it could have been - or the net run-rate swing as great - after Australia brutally reduced Ireland to 25-5 inside four overs.
Ireland's number three Lorcan Tucker held firm with a brilliant 71 not out from 48 balls to spare Ireland humiliation and prolong the innings, much to the relief of England supporters.
Ireland were poor with the ball, bowling 13 wides in the 20 overs.
There were five in one 11-ball over from seamer Mark Adair, as Finch and Marcus Stoinis, who hit 35 from 25 balls, took full advantage.
Finch, though, limped off the field with a hamstring injury in Ireland's chase, a further dampener on what was turning into a perfect night for Australia.
Australia's Matthew Wade, speaking to BBC Test Match Special, said: "That [net run-rate] did go out of the window a little bit.