Chelsea legend Frank Lampard returned to Stamford Bridge on Wednesday night and gave the Blues a wake-up call.
Lamps brought his Derby side, already winners at Manchester United, for a League Cup last-16 clash and lost 3-2 only due to two own goals from Fikayo Tomori and Richard Keogh, but twice Derby came back before Cesc Fabregas’ winner.
And Blues assistant coach Gianfranco Zola reckons their defence needs to improve ahead of Sunday’s Premier League match against Crystal Palace.
Zola says: “It was a tough game. Derby were excellent. They created us more problems. Our defence wasn’t as good as other times. But most of the problems were created by them.
“We were lucky on occasions.”