Premier League clubs spent a record £3 billion ($4 billion) in a summer transfer window that finished with a bang thanks to Liverpool's £125 million ($169 million) signing of Newcastle United striker Alexander Isak .

The figure, as estimated by finance company Deloitte, smashed the previous record of £2.36 billion two summers ago.

Liverpool spent more than £400 million in the window, a record for a Premier League club, with Arsenal , Chelsea , Manchester United and Isak's former club Newcastle all breaking the £200 million barrier.

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Tim Lunn, director in the Deloitte Sports Business Group, told the PA news agency:

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