Willian admits he "really wanted to stay" at Chelsea and that his move to Arsenal in the summer transfer window "wasn't easy".
The Brazilian forward left Chelsea when his contract expired at the end of last season and joined London rivals Arsenal on a free.
Willian was a popular figure at Stamford Bridge, but after making a bright start for the Gunners has seen his form decline in recent months.
The 32-year-old is yet to get on the scoresheet for his new club, and he's now reflected on his summer move, which he admits was very difficult for him.
"It was difficult to make that decision, it wasn't easy," Willian told UOL. "Because, as you said, the rivalry between the two clubs is very big.
"It wasn't an easy decision to leave Chelsea for Arsenal. It was well thought out, a thoughtful decision, talking to my wife and even the agent many times.
"And one of the things that made me decide to go to Arsenal was really the various conversations I had with Mikel Arteta, with Edu too.
"They convinced me to go there that it'd be a really cool project, that it’d be really good for me to be able to go there. That I'd be a very important player in the squad.
"That they wanted to change the philosophy of the club, to make it possible for Arsenal to fight again in the Premier League, to play in the Champions League again.
"So there were several conversations I had, several conversations that ended up pleasing me, so that's why I ended up making this decision.
"But it really wasn't easy to make that decision, it had to be well thought out.
"Look, I think some fans asked this question. But the majority understood because I didn't leave the club with a fight, I left the doors open.
"Everyone knew the conditions, I really wanted to stay. We ended up not finding an agreement, I ended up asking for three years, Chelsea wanted to give two, and everyone knows this story. That's why I ended up leaving."
