Australia captain Meg Lanning broke her own record for the highest individual score in a women’s T20 international by hitting 133 against England.
Lanning cracked 17 fours and seven sixes as she finished unbeaten off 63 balls in Australia’s total of 226-3.
The 27-year-old topped the previous best of 126, which she set in March 2014 and was then equalled by Sterre Kalis of the Netherlands last month.
Australia’s tally means England face a record run chase in T20 internationals.
To win they must beat their own tally of 199-3 against India in Mumbai last year.
Australia will retain the Ashes with victory in Chelmsford as they have an 8-2 lead in the multi-format series, although England can still draw the series if they win all three T20 games.
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