Juventus have officially announced the signing of Arthur from Barcelona for £72.5 million.
The midfielder completed his medical at the Italian club on Sunday but was seen training with Barca on Monday. A video emerged of him seemingly saying his goodbye in a huddle on the training ground.
Arthur will earn £4.5m (€5m) per year in Turin, an increase on his current wage at Barcelona.
Miralem Pjanic will be going in the opposite direction for a fee worth around £60 million - although that deal is yet to be confirmed by either club.
Arthur signed a six-year contract at Barca in the summer of 2018, after signing from Gremio for an initial £27 million.
The midfielder played 27 times in La Liga in his debut campaign, failing to score. This season, he's played 20 matches in the league, scoring three times.
He's also been capped for his country on 20 occasions.
Despite previously insisting that he wanted to stay at the Camp Nou and fight for his place, the Catalan club were happy to sell him to raise much-needed funds to invest in their squad.
Meanwhile, Juve boss Maurizio Sarri reportedly wants to build his side around Arthur - much like he did with Jorginho at Napoli and Chelsea.
Despite agreeing to join Juve, Barca boss Quique Setien insisted he had no doubts about Arthur's commitment between now and the end of the season.
"I have no doubt about his greatest commitment until the last day he is here," Barca head coach Setien said on Monday.
"He is a player until the last game of the season He has committed himself to being one more [member of the squad].
"He will dedicate himself fully to achieving the objectives. I have no doubts about him.
"He has said that he will be in the best conditions. I'll decide if he plays more or less."
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