Frank Lampard returns to Chelsea with his Derby County side on Wednesday, with the Rams taking on the Blues in the fourth round of the Carabao Cup at Stamford Bridge.
Derby pulled off a shock in the last round, beating Manchester United at Old Trafford on penalties. Lampard's side are also flying high in the Championship and go into the game in sixth place.
Yet the Premier League side will be hot favourites to progress. Maurizio Sarri's side remain unbeaten in the Premier League and beat Liverpool at Anfield in the last round.
Date: Wednesday, October 31
Time: 7:45 p.m. GMT/3:45 p.m. ET
Venue: Stamford Bridge, London
TV Info: Sky Sports Football (UK)
Odds according to Oddschecker
Chelsea will meet some familiar faces when Derby come to visit. Not only will former star Lampard be back at Stamford Bridge, but loanees Mason Mount and Fikayo Tomori will also return.
The Blues confirmed they have granted permission for both players to play in the match and face their parent club:
Chelsea said they "believe the experience of facing top-level opposition once more will be of benefit to their ongoing development."
Derby do have concerns over Mount's fitness, however, according to Liam Twomey at ESPN FC:
Lampard has said he expects the 19-year-old to play, per Steve Nicholson for the Derby Telegraph.
Mount has made 16 appearances for Derby this season, scoring five times. His performances have also seen him called up to the senior England squad by Gareth Southgate for October's UEFA Nations League games against Croatia and Spain.
Lampard has said the decision to let both players feature is a "classy move" by his former, side, per Football.London's Avinash Bhunjun.
Derby's victory at Manchester United last time out has shown they have the ability to pull off a surprise, but repeating that victory at Stamford Bridge is a tall order.
Sarri will rotate his side but still has plenty of quality options who could come into consideration. Ruben Loftus-Cheek, who has four goals in his last two games may feature, while talented 17-year-old Callum Hudson-Odoi will also be hoping for game time.
Chelsea are in excellent form with 12 goals scored in their last four games alone. Derby may prove awkward opponents, but anything other than a home win will be a surprise.