Everton have now slapped a massive £65m valuation on Lukaku in an attempt to fight off interest from Chelsea, Paris St-Germain, Manchester United and Real Madrid.

Everton are also reluctant to allow Lukaku to leave for a club that will not be in next season’s Champions League, such as Chelsea, but they would have had no choice if the Blues had a buy-back option.

According to sources close to the deal in Belgium, Chelsea missed their chance to make sure they could re-sign Lukaku for a cut-price fee, regardless of opposition from Everton, thanks to former manager Mourinho.

Chelsea had been open to the idea of accepting a lower fee for Lukaku from Everton and including a buy-back clause in the deal so that he could easily be taken back to Stamford Bridge.