Michael Olise scored twice on either side of Jean-Philippe Mateta and Tyrick Mitchell’s goals to condemn Erik ten Hag’s side to a 13th Premier League defeat of the season.
The embarrassing performance and result increased United’s chances of suffering a record-low eighth-place finish, which would deny the club European football next season.
Several of the visitors’ players were accused of throwing another manager under the bus in South London, having been outfought and outclassed for the entire match.
However, eight of those who featured were signed by Ten Hag across the past two years, including Andre Onana, Mason Mount and Antony.
After full-time, cameras shot the trio in deep conversation as they slowly walked towards the tunnel, covering their mouths as if they wanted it to remain private.
And on Sky Sports’ Monday Night Football, Carragher interrupted host Dave Jones to tear into the three players for their actions.
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“Just get off the pitch! I mean, talking, whispering behind your hand… you’ve been absolutely awful,” Carragher ranted.
They’re probably talking about one of the players or somebody else or the set-up or the manager.
“Just get off the pitch, shut up and get in. You’ve been beaten 4-0, whispering, talking about other players. Honestly, embarrassing.”
Andre Onana produced six saves to prevent further humiliation but was beaten four times and fielded criticism for his anticipation of shot angles.
Meanwhile, Mason Mount was handed a huge opportunity to impress in the first-ever club match Bruno Fernandes missed due to an injury.
However, he underwhelmed, and the question of why United splashed £55million to sign him after he entered the final 12 months of his Chelsea contract is yet to be answered.
And not much more can be said about Antony. Ten Hag’s push to splurge £86m to bring him to Old Trafford from Ajax will go down as one of his most costly failures.
The Brazilian winger was woeful on the ball, bickering with his attacking teammates after he misplaced passes more often than producing anything of substance in the final third.
Sir Jim Ratcliffe is reportedly planning a clearout this summer. He saw just how ruthless he needs to get on Monday night.
