Half-time: Derby 0 Chelsea 1 – Blues ahead but Zouma suffers injury
Eden Hazard’s clinical low strike put Chelsea on course for the Capital One Cup semi-finals but the first half was marred by an injury to Kurt Zouma.
Hazard anticipated Richard Keogh’s sloppy pass out of defence and controlled the ball neatly before racing towards goal, cutting inside and finding the bottom corner.
But just before the interval Zouma had to be taken off on a stretcher after lengthy treatment when he was clattered by Petr Cech as the Blues goalkeeper cleared a corner.
Derby, with Will Hughes and Omar Mascarell impressing in midfield, started brightly and had a couple of threatening moments.
But the visitors settled and, with Didier Drogba in dominant form and Andre Schurrle and Hazard dangerous on the break, they posed the greater goal threat.
Drogba came closest to adding a second but his goalbound effort, after great work by Schurrle, was blocked by Keogh.
The Blues survived some sustained home pressure after which Branislav Ivanovic replaced Zouma following a near 10-minute delay.
Chelsea: Cech; Azpilicueta, Zouma (Ivanovic 45+3), Terry, Luis; Matic, Mikel; Hazard, Schurrle, Fabregas; Drogba.
Subs: Schwarzer, Ramires, Salah, Willian, Remy, Costa.
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