Newcastle boss Kevin Keegan has been holding talks with the Magpies board as speculation mounts over his future, BBC Radio Newcastle understands.
Reports have suggested that the 57-year-old has been unhappy with a lack of control over transfer activity.
Their only business on transfer deadline day was a £5.7m swoop for Spanish striker Xisco and the loan signing of midfielder Ignacio Gonzalez.
Keegan was only appointed in January, having first managed there from 1992.
<!-- E SF -->
The transfer window saw the arrival of six players at St James' Park, with five players leaving the club.
James Milner was one of those who left last week, transferred to Aston Villa for a fee of £12m, with Keegan admitting it had been difficult to see the 22-year-old leave. <!-- S IBOX -->
<TABLE cellSpacing=0 cellPadding=0 width=208 align=right border=0><TBODY><TR><TD width=5>
To view links or images in this forum your post count must be 20 or greater. You currently have 0 posts.</TD><TD class=sib606><!-- E ILIN -->
</TD></TR></TBODY></TABLE>
<!-- E IBOX -->
BBC Radio 5 Live football reporter Juliette Ferrington said: "It is thought that the sale of players and the failure to replace them brought this meeting to a head.
"It has been rumoured over the last few months that his relationship with the club's board has been strained," she said.
Keegan has also supported Joey Barton, after the controversial midfielder spent 74 days in jail for an assault conviction.
Barton will also be attending a personal hearing on Friday after admitting a Football Association violent conduct charge.
Ferrington added: "My understanding is that there was a disagreement over Joey Barton about a potential transfer to another Premier League club.
"Kevin Keegan wanted him to stay, and of course he gets his way but I'm told the board wanted to sell him."
One appointment two weeks into Keegan's tenure that caused controversy was Dennis Wise, taken on board to oversee transfer activity.
<!-- END - caption --><!-- end of the embedded player component --><!-- END of Inline Embedded Media -->
The manager's relationship with owner Mike Ashley was also reported to have soured in May this year, after Keegan claimed that Newcastle were unlikely to break into the top four during his time in charge.
Fans were gathered in their hundreds outside St James' Park on Monday, angered by the suggestion Keegan's position could be in doubt.
Frank Gilmour, of the Independent Newcastle United Supporters' Association, said: "It's an absolute farce, you cannot run a football club like this."
The former Fulham, England and Manchester City boss, who also managed the club from 1992 to 1997, returned to St James' Park for a second time in January following the sacking of Sam Allardyce.
He walked out on the club during his first spell in charge in January 1997, citing off-pitch interference.
"This is on a par with what happened 11 years ago. I wouldn't blame Keegan for going whatsoever," said Gilmour.
The club are 11th in the Premier League having picked up just four points from their opening three games. <!-- E BO -->