Manchester United boss Erik ten Hag has promised that his squad have been left "in no doubt" that the performance they put in at Liverpool will not be tolerated.
The Red Devils shipped six second-half goals at Anfield to fall to a dire 7-0 hammering at the hands of their fierce rivals. It was a result and a display that left Ten Hag furious, with the Dutchman forcing his side to sit in silence and listen to the Reds' celebrations.
They have the chance to get their season back on track on Thursday night with a clash against Real Betis in the Last 16 of the Europa League. And ahead of that game, Ten Hag has promised supporters that his side have learnt lessons from their abysmal performance at Anfield.
In his programme notes, the United boss made it clear that he found his side's display on Sunday unacceptable. He also pledged that his squad would realign themselves with the "rules and principles" he has laid down since taking over.
"There are some performances and results which cannot be quickly forgotten, and our defeat at Anfield is an obvious example of this. It is not acceptable for Manchester United to lose in that fashion to any team, but especially not to Liverpool," Ten Hag wrote.
"I want to make clear to you, our fans, that I share your bitter disappointment about the result, and the players have been left in no doubt that we cannot tolerate what we saw in the second half on Sunday.
HAVE YOUR SAY! How would you rate Erik ten Hag's first season at Manchester United? Comment below.
"Me, the staff and all the players have to take joint responsibility and learn from what went wrong. For the players, the two main lessons are clear. In the first half, we saw what happens when you don't take big chances in tight games, and when you lose concentration for just a moment.
"In the second half, we saw what happens when you don't stick together and keep your discipline as a group. We forgot all the rules and principles which have been delivering good results for us since returning from the World Cup, and we were punished harshly.
"The only good thing about such a result is that it removes any complacency that might have been creeping in after recent positive results and shows us the hard work still needed to get this team to the level we want to be at."
United defeated Barcelona to reach this stage of the competition and have also already won the Carabao Cup this campaign. It represents a positive return for Ten Hag's first year in charge.
But the players will need to take heed of Ten Hag's programme notes, having developed a tendency to suffer big losses. Brentford, Manchester City and now Liverpool have all put at least four goals past them in one game.
Ten Hag will be hoping Sunday's performance was the last repeat of such a woeful performance. They are still in with a shout of adding the Europa League and FA Cup to their trophy cabinet but will need to avoid hammerings like Sunday's.