The Manchester clubs' combined £322m ($417.41m) expenditure made up over 40 per cent of the league's total 794 million pound summer spending since May.

United paid a world record fee of £89m to bring Pogba back to Old Trafford from Juventus on Tuesday, while City signed England defender Stones from Everton for £47.5m pounds later that day.

The Manchester rivals have also spent big on the likes of Ilkay Gundogan, Nolito, Leroy Sane (all City), Henrikh Mkhitaryan and Eric Bailly (both United), and both clubs have a summer net transfer spend of over 40 per cent of their annual turnover.

The spending power of the Manchester two underpins the dominance of the 'Big Six', with Arsenal, Chelsea, Liverpool, Tottenham Hotspur, City and United spending £529m since May, twice as much as the rest of the league combined, according to Spreadex's figures.

The outlay of the Big Six dwarves the league's average spend per club of 23 million pounds, while only four sides have turned a profit to date this summer.

Southampton, who sold Sadio Mane to Liverpool for £34m, Graziano Pelle to Shandong Luneng for  £13m pounds and Victor Wanyama to Spurs for £11, have made the greatest profit of the division to date, with £40.

Everton, Swansea City and Hull City are the other teams to have made a net transfer profit so far this summer.