Aaron Finch returned to form with a timely half-century but finished under a hamstring injury cloud as Australia eased to a 42-run win over Ireland at the T20 World Cup on Monday to keep their semi-final hopes alive.

Captain Finch’s 63 off 44 balls helped the hosts post an imposing total of 179 for five at the Gabba in Brisbane before Australia’s bowlers led by Mitchell Starc terrorised Ireland’s top order on Halloween.

Australia moved to second in Group 1 behind leaders New Zealand, who have a game in hand, but the hosts missed a golden opportunity to lift their net run-rate above thirdplaced England after reducing Ireland to 25 for five early on.

A brave, unbeaten 71 by Lorcan Tucker rallied Ireland to 137 before they were bowled out after 18.1 overs.

Tucker was dropped on 35 by Pat Cummins, leaving bowler Starc fuming. “We didn’t get it in the right area enough (to Tucker),” Starc said.

With the top two teams advancing to the semis, the pressure is on England to take down unbeaten New Zealand at the same venue on Tuesday.

Australia have other injury worries apart from Finch. No.6 batsman Tim David was also spared of fielding duties with hamstring soreness. Marcus Stoinis was also on and off the field.

Brief scores: Australia 179/5 in 20 (Aaron Finch 63, Marcus Stoinis 35). Ireland 137 in 18.1 (Lorcan Tucker 71; Glenn Maxwell 2/14, Adam Zampa 2/19). Australia won by 42 runs.