The Brazilian moved to the Emirates Stadium in the summer from Chelsea after his contract expired with the Blues.
The 32-year-old signed a three-year deal with Arsenal and big things were expected of him given his Premier League pedigree.
Willian, however, has struggled at Arsenal and he has now lost his place in Mikel Arteta’s starting XI.
The forward has confessed his performances have not been good enough so far, but he is determined to get back on track.
“To be honest sometimes it can be difficult to explain,” he said.
“The first game was great for me, against Fulham, I felt I had a good performance and gave two assists. And then, I don’t know.
“I’m always trying to do my best, sometimes things don’t go the way you want. You have to say it’s a part of football and a part of life. Sometimes you have good moments, other times you have bad moments, you have to learn from that.
“And right now, I know I’m far away from being at my best, but I’m determined to work hard and change this.”
Willian says he has spoken with Arteta about his poor form and the Spaniard is backing him to come good.
“Of course we walk about lots of things, and I know I have his support,” Willian told Arsenal’s programme.
“That’s great for me, and to have the support of the club, so what I can do is always work hard, give my best in training to try to improve myself.
“This is the only way to get back to good performances.”
