Matty Longstaff is set to join Udinese after being offered £30k a week – double Newcastle's valuation.
The England U21 midfielder is out of contract at the end of the season and has held talks with the Italian club.
The current regime at St James' Park refuse to match the deal, and the only hope of Geordie Longstaff staying is if a takeover is completed and new owners move to protect their asset.
Newcastle will only be due around £400,000 compensation for developing Longstaff whose brother Sean is also looking for a new deal on Tyneside.
Newcastle are willing to hand the younger Longstaff around £15k-a-week, which is 15 times more than his current academy contract.
But they are unwilling to go anywhere near the £30k-a-week on offer from the Serie A side.
The club now has a major dilemma and may have to pay over the odds in wages to keep the youngster and ensure they keep an player who under contract could develop into a £20m-plus first team regular.
Toon boss Steve Bruce had previously admitted Longstaff's contract situation was a "concern".
But he hoped that Longstaff's decision was motivated by football and not money.
“Of course the situation is a concern,” Bruce said. “I just hope that he looks at it as a football decision. Ultimately, when you’re 19, it is about how you look after your career rather than anything else.
“I’m sure there are distractions and people in his ear. I hope he just looks at it as a football career.
“At the end of the day, if you have a successful career, money will find you. That’s always been my philosophy on it.
“He’s a 19-year-old who has done very well. Tell me another 19-year-old who’s played in the Premier League this year? There’s not many.
“I’ve made big decisions around him and left people out to play him. I hope he finds a conclusion with the club, I really do.
“We all want him to stay, but players have this prerogative. Of course, it’s a concern, but we can only do what we can do.”
