The Frenchman spent three years in West London following his move from Arsenal, before leaving the club last summer to join AC Milan. He scored 11 league goals in his first season with the club and helped them to the Serie A title.
He now returns to England with Milan to face the Blues on Wednesday night, with successive matches between the two sides set to play a decisive role in what is an incredibly tight Group E.
Milan are in pole position as it stands after taking four points from their first two games, while the pressure is right and true on Chelsea, who are bottom. A defeat to Dinamo Zagreb and a draw to RB Salzburg is all they have done so far.
“Yes, of course,” Giroud replied when asked if he had told his teammates what to expect at Stamford Bridge.
“But I told them at this point as we walked across the pitch that I am very proud to come here with the great Milan to play the Champions League, play in our colors and defend our badge.
“It will be an atmosphere worthy of a Champions League match. They have played big games and won big games. But we are ready.”
He added: “I was lucky enough to return to Montpellier when I played for Arsenal in my first game in the Champions League.
“And today I am very happy to be back at Stamford Bridge. I want to show how good Milan is, we showed our quality in Italy last season to win the league.
“But now we want to do the same and repeat it in the Champions League.
Graham Potter took his first win as Chelsea boss this weekend as Conor Gallagher scored a stunning late winner against his former club Crystal Palace to make sure the Blues wouldn’t have another frustrating result.
He knows immediate results are needed in Europe if Chelsea are to get out of the group, with AC Milan boss Stefano Pioli expecting the Englishman to give the visitors a hard time at Stamford Bridge.
“I know Graham Potter because Brighton played very well and I followed them for a long time,” said Pioli.
“He’s a really good coach, he really has an attacking game plan. It’s true they’ve only played two games with their coach, but he’s changed systems several times in those games. So a lot has changed.”