Arthur has been photographed wearing Barcelona's shirt for the 2017-18 season. The midfielder, who starred in Gremio's Copa Libertadores triumph, appeared in the image on Friday in Porto Alegre.
The Brazilian international, who won the Copa on Wednesday, is being followed by the Catalan club.
Without going any further, Robert Fernandez has spent eight days in South America to see the two legs of the final: Gremio won the first leg against Lanus 1-0 and the second leg in Buenos Aires 2-1.
Arthur was named the MVP of the final.
SPORT revealed on Thursday that Robert had held a meeting with the midfielder's agents after the first leg of the final, dining at a restaurant in Porto Alegre.
In the photograph, Arthur is accompanied by Barça director Andre Cury, the club's man in South America.