Chelsea striker Olivier Giroud says they should be positive after seeing off Europa League opponents Slavia Prague 4-3 on Thursday.

A double from Pedro, Giroud's 10th Europa League strike and an own goal by Simon Deli had Maurizio Sarri's side in control with a 4-1 lead at the break.

But another woeful performance after the interval nearly cost them dearly as Slavia Prague struck two goals through Petr Sevcik to ensure a nervy ending at Stamford Bridge.

Giroud said: "We started well with good intentions. We have been efficient up front and solid at the back but we dropped our intensity after the break. This team never gives up and the last 10 minutes was box to box.

"It was a good fight and now we are in the semi-finals."