Matthew Hayden and Ricky Ponting made centuries and shared a 200-run second-wicket partnership as Australia scraped in an eight-run win over New Zealand in their tri-series limited-overs match.Hayden made 117 from 111 balls and Ponting 111 from 122 as Australia reached 343 for five after winning the toss and batting first; the highest score by any team in a limited-overs match at the WACA Ground.Jacob Oram smashed 101 not out from only 72 balls, putting on 137 in an unbroken partnership with Brendon McCullum (46 not out), as New Zealand reached 335 for five in reply, failing only narrowly to overhaul Australia’s massive total.Oram’s century from 71 balls contained four fours and six sixes and was the fastest by a New Zealander in limited-overs internationals. It was also his first ODI century and eclipsed his 86 at Adelaide last week as his highest limited-overs score.“We were chasing two runs a ball at the end so I just kept on swinging as hard as I could,” Oram said. “It was thoroughly enjoyable and very satisfying, but disappointing to lose, of course.”Lou Vincent gave New Zealand’s innings a solid foundation with a score of 66 from 82 balls. Australia put down several catch chances, but their excellent ground fielding helped them to their sixth straight win of the series.Hayden and Ponting’s 200-run stand for the second wicket had already made New Zealand’s task almost impossible. Ponting batted in Hayden’s shadow early in his innings but reached his half century from 62 balls and his century from 113 deliveries. Later Michael Hussey smashed 29 from 16 balls and Cameron White 24 from 12 balls for an unbroken stand of 50 for the sixth wicket. That partnership was eventually the difference between the teams.Brief scores: Australia 343/5 (Matthew Hayden 117, Ricky Ponting 111; Daniel Vettori 1/34) beat New Zealand 335/5 (Jacob Oram 101 not out, Lou Vincent 66, Brendon McCullum 46 not out; Michael Clarke 2/48).