Middlesbrough chairman Steve Gibson is demanding an English Football League investigation into the financial conduct of three Championship rivals.

Gibson wants the EFL to scrutinise Derby County, Aston Villa and Sheffield Wednesday over what he believes to be breaches of financial regulations, in a move which could trigger a bitter dispute between the clubs.

The 61-year-old is insisting the three clubs are attempting to bypass the new profitability and sustainability rules by unfair means, and he has arranged a special meeting of all Championship clubs for a week on Wednesday.

Gibson is understood to be “furious” that Middlesbrough have sold over £40 million worth of players, including Adama Traore, Ben Gibson and Patrick Bamford, to balance the books, while in his view other clubs are manipulating the rules by allocating some costs to stay in line.

Derby, for example, recently sold their Pride Park stadium to owner Mel Morris and then leased it back to ensure the club recorded a profit in their 2017/18 accounts.