Lanning’s side lost by three runs to England at Bristol overnight, Australian time, after failing to chase down the home side’s 8-259 – finishing 8-256 in reply.
Australia had England on the ropes at 6-174 before an 85-run stand between Katherine Brunt and Jenny Gunn for the seventh wicket helped them to a defendable total.
After an opening stand of 56 between Beth Mooney (31) and Nicole Bolton (26) the visitors appeared on track when Elysse Perry (70) and Lanning (40) combined to get to 3-129 in the 32nd over.
However, with the run rate necessary climbing the fall of regular wickets, including those of Alex Blackwell (21 from 17 balls) and Alyssa Healy (14 from six balls) left Australia needing 16 from the final over.
Jenny Gunn held her nerve for the hosts and even took the wicket of Ashleigh Gardner for 11 to end a 24-year wait for an England victory over Australia at the World Cup.
After bowling well at the start of England’s innings, Australia did themselves no favours by conceding 32 extras and Lanning was frustrated at her side giving away cheap runs.
“The period of overs 30 and 40 was what cost us in the end,” Lanning said.
“We did well towards the end to make a game of it but we left ourselves with too much to do.
“Me and Pez had established a good partnership then I got out which wasn’t ideal and we lost a bit of momentum.
“We’ve spoke about it a fair bit as a bowing unit trying to minimise those extras.
“Thirty-two is way too many and something we are going to have to improve on as we would be chasing a much smaller total.”
Despite their result, England spinner Alex Hartley insists Australia are still the team to beat.
“Definitely,” Hartley said.
“We’ve got to play a semi-final before we get to a final hopefully.
“Every team in this tournament is capable of beating each other, the results in this tournament over the past couple of weeks have shown, India beating us then South Africa beating India yesterday.
“They’re (Australia) the team to beat but everyone capable of beating each other.”
Tammy Beaumont top scored for England with 49, while part-time medium pacer Elyse Villani was Australia’s chief wicket-taker with 3-42 from five overs.
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