Steve Bruce and Matt Ritchie were reportedly involved in a furious training ground bust-up in the wake of Newcastle's 1-1 draw with Wolves at the weekend.
The Magpies sit just three points off the relegation zone and the pressure is beginning to grow on Bruce at St James' Park.
They looked like they could be set for a much-needed win in Saturday's game when Jamaal Lascelles put them into the lead.
But Ruben Neves equalised for the visitors in the 73rd minute - with Bruce seeming to blame Ritchie for the goal after the game.
He said in an interview: "The instructions Matty didn’t get on to the team quick enough on how we were doing it. When you look at the goal, we should have stopped the cross and when the ‘keeper looks at it, could he have done better?"
According to the Daily Mail Ritchie was left furious with this public criticism - and confronted Bruce about it at training on Tuesday.
It is claimed Ritchie initially phoned his manager about the issue after the match, but was told to wait until training to deal with it.
In Tuesday's session, Bruce is believed to have asked to see Ritchie in his office, but the player refused, and brandished his boss a "coward".
This then led to a blazing argument between the two men, which ended in Ritchie saying he was "done" with Bruce.
The most worrying aspect for Bruce is that the majority of the players allegedly sided with Ritchie in the row, and it is looking more and more like he has lost the dressing room.
It appears highly unlikely that Ritchie will be involved when Newcastle take on fellow strugglers West Brom on Sunday.
But a defeat could well see Bruce handed his marching orders, especially as it could see the side slip into the bottom three.
