Image credit: Eurosport
The Frenchman opened the scoring, picked up an assist for Eden Hazard and also won the penalty for Hazard's first goal.
Giroud was dumped by Arsenal in January 2018, as they sold him to Chelsea for £18m to help finance their move for Pierre-Emerick Aubameyang - who had an awful game in Baku.
'It's difficult to find a player like him' - Chelsea stars react to Hazard news
And the striker seemed keen to remind his former employers of their decision to get red.
"Thank you Arsenal!" he shouted on the team bus as Chelsea celebrated their European title.
The video was posted on team-mate Jorginho's Instagram.
Phillip Island, Australia
Round 6, Rabat