LONDON -- Frank Lampard tasted defeat on his first trip to an adoring Stamford Bridge as a manager, falling 3-2, but not before his vibrant Derby County side gave Chelsea a significant scare in the Carabao Cup fourth round -- with returning loanees Mason Mount and Fikayo Tomori both making an impact.
Chelsea are through, Mount and Tomori got some valuable big-game experience, and Stamford Bridge got to pay tribute to perhaps the club's biggest legend without the night being tainted by an upset defeat (just about).
Maurizio Sarri will not be happy with how much his second string were troubled by Derby's high press, particularly in a frantic first half. It's hard to make a case for any of the fringe players given an opportunity here to start in the Premier League against Crystal Palace on Sunday.
Manager rating out of 10
7 -- Sarri gave many of his frustrated reserves an opportunity and was almost let down, but deserves credit for whatever he said at half-time. Chelsea were a little more controlled after the break and the manager's substitutions helped.
Player ratings (1-10; 10 = best. Players introduced after 70 minutes get no rating)
GK Willy Caballero, 6 -- Could do nothing about either of Derby's goals, but his distribution was poor and nothing about him inspired confidence in his defenders. Admittedly though, they in turn did him few favours. Made a big save to preserve Chelsea's lead in the final minutes though.
DF Davide Zappacosta, 6 -- Provided two assists with dangerous crosses, though it's hard to know how much credit to give him when they both found Derby players. His forward runs were just as dangerous to Chelsea as to the opponents; both visiting goals came from the space vacated on his flank.
DF Andreas Christensen, 6 -- Unsettled by the speed and ferocity of Derby's pressing, he played his way into trouble a few times in a manic first half. Managed to stabilise himself in the second, but this isn't the display that will persuade Sarri to pick him over David Luiz, who eventually replaced him.
DF Gary Cahill, 5 -- His relative lack of comfort in possession and mobility are the main reasons why he has spent so much time on the bench this season, and Derby targeted the limitations in his game with their fast attack. Compounded a bad pass to Cesc Fabregas with a costly slip in the build-up to Jack Marriott's goal, and David Nugent ran in behind him to hit the post late on.
DF Emerson Palmieri, 5 -- Has plenty in his locker going forward and embarrassed Jayden Bogle with one slick run, but defensively his positioning and decision-making were a liability. Marriott and Martyn Waghorn managed to get in behind him early and often.
MF N'Golo Kante, 7 -- Showed no sign of fatigue in a game he wasn't expected to start and made life particularly difficult for Mount on his Stamford Bridge return. Also combined well with Ruben Loftus-Cheek and Zappacosta on the right.
MF Cesc Fabregas 6 -- His long-range passing was off and he was caught out for Derby's first goal, but timed a run into the penalty area perfectly to score Chelsea's crucial third goal with their first shot on target.
MF Mateo Kovacic, 6 -- It felt like a statement when he shot from 20 yards the first time he got the ball. Tidy as ever but a lack of final-third impact is what has allowed Ross Barkley to jump ahead of him and, judging by the persistent chants of "Shoot!" from Stamford Bridge, is becoming more of an issue for fans too.
FW Ruben Loftus-Cheek, 7 -- Deployed on the right wing just as he was against Burnley on Sunday, the academy graduate was Chelsea's best attacking performer on the night. His height and strength made him an outlet when Derby pressed and his powerful running on the ball caused regular panic.
FW Alvaro Morata, 6 -- Was not helped by the rotation around him, but looked a shadow of the player who menaced Burnley and provided a focal point for Chelsea's fluid attack. Tomori and Richard Keogh controlled him better than they could control their own limbs. More of a threat late on but Scott Carson was equal to his best efforts.
FW Willian, 7 -- Starting his 10th match in a row, the Brazilian brought the poise and guile to Chelsea's front three with his direct dribbling and close control. A meaningful end product, however, eluded him.
DF David Luiz, 6 -- Brought on for Christensen to give Chelsea greater defensive solidity, he broadly did his job as Derby pushed in vain for an equaliser in the final 20 minutes.
FW Pedro, 6 -- Looked well enough physically after leaving the Burnley game early with severe stomachache, but may take a little longer to rediscover his early-season rhythm in the final third.
DF Cesar Azpilicueta, N/R -- He came on for Zappacosta in the final minutes as Sarri tried to shore things up.