Newcastle's official Fans Forum has called on the club for "action" as speculation about head coach Steve McClaren's future continues to intensify.
Saturday's 3-1 home defeat to Bournemouth saw anti-McClaren chants and boos from Magpies supporters ring around St James' Park.
It was the Tyneside club's 16th Barclays Premier League loss of the season, their fifth in their last six games, leaving them second-bottom of the table with 10 matches to play.
McClaren vowed in his post-match press conference on Saturday that he would not be resigning, but talk is rife that the 54-year-old is facing the sack, with former Newcastle owner Sir John Hall on Sunday saying he should be axed.
While Newcastle are yet to comment on McClaren's position, reports on Monday suggested the board, of which he is a member, was holding discussions about the situation without him.
Meanwhile, an open letter to the club from the Fans Forum - which has 15 seats occupied by supporters representing different elements of Newcastle's fanbase, and meets to put questions to club officials at various points during a season - was published.
It said: "What NUFC fans want is a team of 11 players in black and white shirts that understand their role to perform to their maximum - week in, week out.
"We have entrusted the board of NUFC to ensure that the right personnel are in place to carry out this basic expectation.
"Whilst we still have 10 games to go, NUFC Fans cannot accept the current work ethic of the players.
"Someone, somewhere has to be accountable and decisions must be made.
"We must urge you to review our position and initiate any changes you see fit to correct the current attitude of the playing staff.
"Our players frequently look jaded and our playing style often appears outdated. We lack organisation and the players continue to lack discipline.
"Maybe it's time to accept that the 'Head Coach' role simply doesn't work at NUFC and accept that a Manager is required, a person who will not only coach but motivate and manage!
"We want players that are proud to wear the famous colours. We want a manager that truly wants the best for us.
"It's time for action, it's time for accountability."