Gary Neville says Ole Gunnar Solskjaer will be under "intolerable" pressure after Manchester United were dismantled 5-0 by Liverpool on Sunday.
The Red Devils were humiliated on their own patch against their biggest rivals, as Jurgen Klopp's side stormed into a 4-0 lead before half-time.
Mohamed Salah completed his hat-trick in the 50th minute and United's misery was compounded when Paul Pogba was sent off on the hour mark.
The scoreline could have been even worse for United had Liverpool not taken their foot off the gas in the final 30 minutes.
Solskjaer's performance as the club's manager was already under scrutiny following a run of three games without a win in the Premier League.
And Neville, who has been a vocal supporter of his former team-mate up to now, admits the Norwegian will come in for fierce criticism after a defeat of this magnitude.
"The pressure after this game is going to be intolerable in some quarters," he told Sky Sports.
"The board have made everyone aware that they are steadfast in their support of the manager and that he stays. Results like this undermine that, there's no doubt. This is sobering.
"Manchester United need to change. I believe Ole Gunnar Solskjaer is going to get the opportunity to change. But there is going to be pressure from every source.
"There's no doubt the manager will get an absolute battering. There will be calls for his head like you wouldn't believe but you wonder what this defeat will do to the players. How will they pick themselves up?
"There's no hiding place after this. United are going to be absolutely demoralised. The next 24 hours is going to be as hot as it has ever been at this football club.
"This is a monstrous day for Man United. That's going to put an enormous amount of pressure on the board.
"The fans haven't turned on the manager in the ground - they never will. But they know that's not acceptable. Something has to change in that dressing room and with this coach and it's got to change very quick."
Despite the nature of the loss to Liverpool, Neville believes his former club will keep faith with Solskjaer.
"It's painful watching that [Solskjaer] interview," he added. "But it's part of the game. It's Manchester United. If this was in the immediate post-Sir Alex Ferguson era, Ole would be under massive pressure tonight.
"But I think the club will hold their nerve. I don't think they've planned for a new manager this season. I think they'll sit with him until the end of the season.
"There'll be a massive outcry from fans and media that Ole should be sacked and I can understand that after that game. It was a monstrously bad day and it takes some recovery from.
"But I think this club is a lot more stable in terms of the ownership - I think now might be the time for them to communicate with the fans if they're going to back the manager for the next six to eight months, which I think they will.
"The reason the board will stay stable is because of what happened with Jose Mourinho, with Louis van Gaal. They won't bring in a hitman again to try and do a job for a couple of seasons."
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