Flashscore sources: Newcastle balancing Guimaraes uncertainty and Manzambi chase
The most significant issue concerns Guimaraes, who continues to attract strong interest from Arsenal and is understood to be open to the prospect of moving to north London.
Newcastle have long recognised that interest in the Brazil international would eventually become a serious issue, although sources indicate they had expected that conversation to develop later in the transfer window, towards the end of July.
Instead, Brazil's earlier-than-anticipated elimination from the World Cup has accelerated the timeline.
With Guimaraes not expected to play a prominent role in Newcastle's pre-season schedule, there is a growing belief that Arsenal could be encouraged to formalise their interest sooner rather than later.
Reports have suggested Arsenal would be prepared to bid somewhere between £60 million and £80 million for the midfielder. However, from Newcastle's perspective, accepting an offer in that range would be difficult to justify after sanctioning Sandro Tonali's £100 million departure earlier this summer.
Losing both players in the same window would represent a significant overhaul of Eddie Howe's midfield and place even greater importance on strengthening that area before the new season begins.
That works to explain Newcastle's parallel pursuit of Freiburg midfielder Johan Manzambi.
The Magpies have been exploring a deal worth around £51 million for the Switzerland international and have held optimism that an agreement with Freiburg could be reached.
However, sources indicate personal terms have yet to be finalised, despite those discussions usually being advanced before clubs settle on a transfer fee.
One factor complicating negotiations is Manzambi's continued involvement at the World Cup with Switzerland, limiting the opportunity to fully progress talks.
There is also increasing concern within Newcastle that Freiburg remain willing to entertain interest from other clubs, raising the possibility that the deal could be hijacked if negotiations are allowed to drift.
As a result, Newcastle are keen to accelerate discussions as quickly as possible.
The two situations are not directly connected, but any movement involving Guimaraes would significantly alter Newcastle's plans in midfield, while equally the club are conscious they cannot afford to miss out on one of their primary targets should competition for Manzambi intensify.
It leaves Newcastle balancing two complex negotiations at the same time as they look to reshape one of the most important areas of Howe's squad ahead of the new campaign.