Giroud completed his flawless hat trick - goals with the left and right foot and one with his head - in the 59th minute with a towering header from a Willian free kick to make it 4-0 as the rout continued.
Here is everything you need to know about the game.
"We were able to score after five minutes".
"Olivier is, for us, a very important player".
"In fact I think he's been very good for Chelsea since he's been at the club, possibly underrated in many respects but proving it again in the Europa League that he can score goals".
"I am a competitor, I want to play every single game and to be happy on the pitch", he said.
Ancelotti's team reached the quarter-finals of the Europa League by beating Red Bull Salzburg in the last 16 stage over the course of the two legs.
Sarri heavily rotated for the match in Kiev, handing rare starts to Ruben Loftus-Cheek in central midfield and Hudson-Odoi on the right wing, and both Chelsea academy products looked sharp at the Olympic Stadium as their team ran riot.
An all-Spanish affair for the second quarter-final.
Maurizio Sarri would surely love to win a trophy during his first campaign in charge at Stamford Bridge and his path to the final has now been mapped out.