Like his team mates, Finn had come in for heavy punishment from Australia's batsmen, who smashed 342-9 from their 50 overs, but grabbed some consolation when he became the first English bowler to take a hat-trick at a World Cup.
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With three deliveries left in the innings, Finn dismissed Australian wicketkeeper Brad Haddin for 31 when he top edged a catch to Stuart Broad at deep third man.
Off the next ball, Glenn Maxwell, who crossed during Haddin's deflection, departed for 66 when he was brilliantly caught by a diving Joe Root at long off.
Then off the final ball of the innings, Mitchell Johnson slapped the ball straight to Jimmy Anderson at mid-off, giving Finn an unexpected hat-trick and figures of 5-71.
Finn became just the seventh player to take a hat-trick at a World Cup.
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Image: Steven Finn of England celebrates after taking the wicket of George Bailey of Australia
Photograph: Shaun Botterill/Getty Images
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