​Newcastle United’s tumultuous summer transfer window continues to be overshadowed by uncertainty surrounding captain Bruno Guimaraes and his future at St. James’ Park.With Anthony Gordon and Sandro Tonali already gone and Arsenal continuing to pursue the Brazil international, the latest developments suggest that Guimaraes has already signaled his willingness to make the move to north London in a very clear way.AdvertisementAdvertisementAdvertisementAccording to football.london, Guimaraes has effectively “given Arsenal the green light to sign him” by informing Newcastle he wants to leave the club this summer.Eddie Howe’s side remains determined to keep its captain and, in a bit of good news, the report states that Bruno is not expected to force an exit in the manner Alexander Isak did before joining Liverpool last year, a behaviour the Brazilian didn’t appreciate last summer.Arsenal, for one, has yet to open formal club-to-club negotiations with Newcastle, but football.london reports the Premier League champions have already agreed personal terms with Bruno’s representatives. An offer worth around £60 million has also been communicated through intermediaries, although Newcastle immediately rejected that valuation and reiterated that the midfielder is not for sale.That stance has been reinforced by a fresh report placing Newcastle’s asking price much higher. According to talkSPORT, the Magpies now value Guimaraes at a ridiculous fee of around £100 million, matching the fee Tottenham Hotspur paid for Sandro Tonali earlier this summer. If you ask me, that feels more in line with a club in love with their captain than a proper valuation of a player and a bit-too-stubborn approach to a sale that could yield a good deal of profit.AdvertisementAdvertisementAdvertisementConvincing Bruno to stay was already going to be hard following last season’s implosion, but this summer transfer window struggles could further complicate those efforts. Not only has Newcastle lost their two best players in Gordon and Tonali, but the club has also missed out on priority targets Victor Munoz and Johan Manzambi after both ultimately chose other destinations.For now, Newcastle remains publicly committed to retaining its captain, but with Guimaraes reportedly open to joining Arsenal and personal terms already in place, attention will now shift to whether the Gunners decide to test the Magpies’ resolve with a formal offer.