Lille striker Olivier Giroud has lifted the lid on the real reason he walked away from Arsenal, admitting he had no choice if he wanted to make France's squad for the 2018 World Cup.
British newspaper "Mirror" report that the French striker left Arsenal in January 2018 to join Chelsea, one of his former club's Premier League rivals.
Arsene Wenger signed him, and Giroud repaid the French manager with 105 goals in 253 appearances for the Gunners.
This week takes him back to north London, where Premier League champions Arsenal host his current club Lille in the Champions League.
Giroud looked back on his Arsenal years, saying: "When I joined Arsenal, my performance improved a great deal thanks to the daily fundamentals we used to work on in training."
He added: "We worked on developing technical skills, and finishing attacks with one touch, as well as building play and the passes that help keep an attack going, playing one-touch to your team-mates, and finishing chances quickly inside the penalty area."
"That was a perfect example," he continued. "I improved a lot in that area, and I became the target man that players could rely on to pass to and use in building attacks. I had a wonderful relationship with my team-mates at that time. Wenger's style was based on quick, smooth football, and it was hugely enjoyable to watch."
The 40-year-old then turned to the modern game: "Clearly the spaces inside the penalty area are now tighter, and teams defend deep and drop back a lot. It is extremely difficult to do that at the moment, but I watch Arsenal a lot, and I notice some similarities in their style of play, as the team always tries to increase the speed of play in the final attacking third."
"You do not want to leave your opponent any space inside the penalty area," he added. "That is a great thing. I can see a lot of similarities between Wenger's team and the current team."
On his decision to go, Giroud said: "That was part of my career and my stage in football. I had to leave the club in order to take part in the 2018 World Cup, and we know how the story ended."
He concluded: "I felt extremely sad to leave the club, but I was forced to take that decision. It was a difficult decision in my career, but it was necessary and important to continue my journey. And it is wonderful to come back at the age of 40 with a French club, and to play against Arsenal under Mikel Arteta."