LONDON: Trent Boult's hat-trick proved in vain for New Zealand as Australia beat their Oceania rivals by 86 runs in Saturday's group match of the Cricket World Cup at Lord's to remain top of the points table.

Boult finished with 4-51 but Usman Khawaja (88) and Alex Carey (71) forged a century-plus stand to help Australia post a competitive 243-9.

Chasing 244 for victory, New Zealand were all out for 157 in the 44th over, with skipper Kane Williamson top scoring for them with 40.

Mitchell Starc (5-26) was the pick of the Australian bowlers in a one-sided rematch of the 2015 World Cup final.