Frank Lampard will have to get dispensation to have loanees Mason Mount and Fikayo Tomori available for Derby's trip to Chelsea in the fourth round of the Carabao Cup.
The Blues legend will return to Stamford Bridge as manager of the Championship club in what will be a special occasion for him personally, having spent 13 years of his playing career in west London.
Lampard's Chelsea connection will no doubt have helped him seal loan deals for the pair, two of the London club's brightest academy products, but EFL rules restrict the use of loanees against parent clubs.