Gary Neville labelled Manchester United captain Bruno Fernandes "embarrassing" and Roy Keane said Erik ten Hag's players should go into hiding after a 7-0 humbling by Liverpool.
Liverpool's three starting forwards – Mohamed Salah, Cody Gakpo and Darwin Nunez – each scored twice, with substitute Roberto Firmino coming off the bench to add to the humiliation.
It was Liverpool's heaviest-ever win over United, their great rivals, and came just a week after the visitors to Anfield won the EFL Cup.
If United's Wembley win pointed to a bright future, this Sunday shoeing on Merseyside was a wake-up call.
United legends Neville and Keane offered no sympathy.
A stunned Neville said after the game: "They've not understood, I don't think, the dangers of this fixture, that when you concede a goal and the crowd get up, it can just swallow you alive and that's what happened today. That Manchester United group of players have been eaten alive in that second half."
During the game, Neville condemned United's defending as "a mess", "appalling", and at 3-0 he said the visitors had "lost their heads".
At 4-0, Neville said United's experienced stars were "playing like schoolboys", and as the scoreline worsened for the men from Old Trafford so the rage increased.
"The second half has been an absolute disgrace, a shambles," Neville said on Sky Sports, "epitomised by no one more than the captain, Bruno Fernandes, who I think has been embarrassing at times.
"It's not their usual performance, it's not their usual spirit, it's not their usual form, and [Ten Hag] will deal with it, I'm sure, very quickly, like he's dealt with other difficult situations this season."
Looking at Fernandes, Neville said: "Some of his behaviour in the second half has been a disgrace."
Keane agreed on that point, saying Fernandes had been "nothing short of disgraceful" in what goes down as the joint-heaviest defeat in United's history, in terms of goal margin.
"You wouldn't be happy with him in your dressing room today," Keane added.
A no-nonsense midfielder and captain in his time, Keane said the result for United made it "obviously a very, very bad day, obviously a shocking day really".
He added: "The senior players, you can use all the words... embarrassing, they didn't show any leadership skills, particularly the senior players, the goals they gave away were shocking.
"Thank goodness I've never been part of a team that's been beaten by that much playing for Man United. The players will be embarrassed and no doubt be ashamed of their performance, particularly the second half when the going got tough and they just went missing to give up that many goals.
"It is the hardest place to come for a Manchester United player. When you go two goals down you've got to show some sort of pride, fight, spirit. They didn't show any of that."
Keane praised Liverpool, saying Jurgen Klopp's team were "brilliant", "back to their very, very best" and "ruthless".
But there was no doubt United let them walk over them.
"The senior players for Man United, the players we give the big build-up to, they're the ones who let the club down today," Keane said.
"I always try and imagine that if you get beaten in a game like this, six or seven nil, you'd go into hiding as a player. I think I'd go missing for a few months. It really is that embarrassing for the players."