Newcastle captain Jamaal Lascelles and team-mate Isaac Hayden had to be pulled apart by staff as anarchy descended following their defeat by Spurs.
The pair were involved in a furious row in the wake of Sunday's 3-2 loss at St James' Park and staff were forced to jump in when they went head-to-head and shoves were exchanged in the tunnel area.
Sportsmail also understands that some players later voiced their unhappiness with Steve Bruce's tactics in the dressing-room.
On a day that was supposed to celebrate the club's new Saudi-led ownership, sources have described how in-fighting and player resentment towards Bruce intensified.