Beth Mooney made a brilliant unbeaten half-century as Australia beat England by six wickets at North Sydney Oval to retain the Women's Ashes with two Twenty20 internationals to spare.

The Aussies went into the first T20 knowing a victory would give them an unassailable 8-4 lead in the series and they finished off the job with ease on Friday.

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Danielle Wyatt (50) top scored for England with a maiden international century in the shortest format, but Megan Schutt took 4-22 as the tourist could only post 132-9.

It could have been much worse for England, which was been in deep trouble on 16-4 before Wyatt, Natalie Sciver (26) and Fran Wilson (23) spared their blushes.

It was still well short of the total required to make a game of it, though, opener Mooney smashing a T20 international best of 86 not out from only 56 balls to get Australia home with 25 balls to spare.

Mooney struck two sixes and 11 fours to get the party started just under a week before the men's Ashes get under way at the Gabba.