Willian is saving Arsenal £20m by walking away from the club to join Brazilian side Corinthians on a free transfer.
Willian has two years left on his £240,000-a-week Arsenal contract but instead of staying at the Emirates or asking for a pay-off, he will tear up his contract and sign for Corinthians in the next 48 hours.
Not only is the 33-year-old saving Arsenal £20m, he is also taking a 70 per cent pay cut to return to his former club.
Arsenal directors are said to be amazed by Willian's gesture.
Willian has been an exemplary professional since he moved to the Premier League eight years ago and he wants to leave English football with his head held high.
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The Brazilian accepts his move to Arsenal from Chelsea last summer has not worked out and he wishes everyone at the club all the very best for the future.
Speaking earlier this week, Arsenal boss Mikel Arteta confirmed Willian has held talks over a move to Corinthians.
"We are having some conversations with him and the agent, and we are evaluating the position that we are in at the moment," Arteta said ahead of Saturday's 5-0 defeat by Premier League champions Manchester City.
"I don't know [why it hasn't worked out for him here].
"At the moment, he is an Arsenal player, and we are trying to get the best out of him while he is here. Anything different is just things that can happen."
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