Gremio have reportedly held talks with Real Madrid over the possibility of the club signing Arthur, having grown angry at Barcelona's approach for the midfielder.
According to Marca's Jose Felix Diaz, Los Blancos have scouted the 21-year-old and he has impressed them with his performances, and "they consider his hypothetical addition to be an interesting one."
Gremio were said to have been "infuriated" by the leak of a photo of Arthur donning a Barcelona shirt alongside the club's sporting director Robert Fernandez. Football journalist Paulo Freitas shared the picture on Twitter:
The Brazilian outfit want his €50 million release clause to be met by any interested parties, but Diaz reported they may not get their wish as they're under pressure to sell because of their "delicate financial situation.