Arsenal are expected to test Newcastle's resolve with a first official bid for Bruno Guimaraes.
The Newcastle captain is said to have informed his club of a desire to leave this summer amid interest from the Premier League champions.
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Standard Sport reported in June that Arsenal had held initial talks with Guimaraes’ representatives to gauge his availability after Newcastle missed out on European qualification.
Discussions proved positive and Arsenal were encouraged to signal their interest, and proposed a bid worth around £55million with the player's camp.
Two weeks later and Arsenal have now received further encouragement from the player and are expected to begin club-to-club talks with Newcastle with an official offer.
Newcastle insist Guimaraes, their best player and current skipper, is not for sale at any price.
The club have already lost Anthony Gordon and Sandro Tonali this summer for a combined £162m, which could rise closer to £170m
It follows the exit of star striker Alexander Isak to Liverpool for £120m last summer.
Guimaraes, 28, has two years left to run on his current contract, and Newcastle hold the option to extend by a further 12 months.
Arsenal have had a low-key start to the summer window. Piero Hincapie's loan move was turned into a permanent deal for £35m, and former Leeds goalkeeper Illan Meslier is set to join on a free transfer.
Brazil were knocked out of the World Cup by Norway on Sunday, with Guimaraes seeing a first half penalty saved. It marked the first time the Selecao failed to make the quarter-final of a World Cup since 1990.
