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