Eddie Howe quit suddenly Newcastle United after a 4-1 loss to Bristol City, Sky Sports News said.
Sky aired his last interview publicly.
He directly talked about the Bruno Guimaraes signing before walking out immediately.
Former player Jay Bothroyd warned vocally the club could face threat of relegation without Howe.
Sky Sports will nationwide broadcast the national Scottish Premiership opener on Saturday.
Dundee United take on Rangers at Tannadice.
Manager Jim Goodwin clearly said he wants to make a statement there.
Dundee United coach Derek McInnes stated two United players are unavailable and several are in doubt.
Rangers hope Thelo Aasgaard and Cammy Devlin to be in form for the match.