Newcastle United continue to publicly resist the sale of their most influential midfielder, according to BBC Sport.
Personal terms between Arsenal and the 28-year-old Brazilian have been in place for some time, with Guimarães having made clear his desire to compete for major honours at the reigning Premier League and Champions League finalists.
Newcastle's public stance has not shifted, but growing signs of resignation are emerging behind the scenes as talks progress toward a fee understood to sit around the £80 million mark, with some reports putting the figure as high as £75-80m depending on add-ons. Arsenal's opening approaches were made verbally through intermediaries rather than as formal bids, contributing to Newcastle's insistence that no direct negotiations have taken place, though momentum in the deal has clearly built in Arsenal's favour in recent days.
A departure would complete a striking summer clear-out at St James' Park, with Guimarães following Alexander Isak, Sandro Tonali and Anthony Gordon out of the club, and arriving just days after Eddie Howe's abrupt exit as head coach.
Newcastle have already begun lining up alternatives in central midfield, with Eintracht Frankfurt's Hugo Larsson and Botafogo's Danilo both under consideration, though Genk's Tommy Froholdt is understood to be the club's preferred target if Guimarães departs.
For Arsenal, landing Guimarães would mark another significant statement in a summer that has already brought in Illan Meslier and Christos Tzolis, with Leandro Trossard sold to Besiktas to help fund the club's business.
Mikel Arteta has pushed hard for the Brazilian personally, viewing him as the player capable of adding steel and creativity to a midfield already tasked with defending both domestic and European titles this season.
Guimarães still has two years remaining on his contract at Newcastle, giving the club leverage in negotiations even amid the upheaval of Howe's departure, and there is no suggestion the Brazilian would agitate publicly for the move in the way some departing players have done elsewhere this summer.
His camp are understood to regard the current window, with the player turning 29 in the coming year, as the right moment for a career-defining step up.