Dimitar Berbatov has unloaded on Manchester United interim manager Ralf Rangnick and captain Harry Maguire following the club's humiliating defeat at the hands of bitter rivals City.
The Red Devils were embarrassed during Sunday's Manchester Derby as the hosts ran out 4-1 winners.
The humiliation saw Rangnick's side lose ground in the race to finish in the Premier League's Champions League places.
Berbatov, who spent four years at United and won two Premier League titles, labelled the entire performance "unacceptable" in a brutal assessment.
The former striker said: "I was angered and saddened by Manchester United's performance against Manchester City.
"It was unacceptable. And I'm not only talking about the second-half."
Join the debate! Do you agree with Berbatov? Give us your verdict here.
The Bulgarian told Betfair: "United had no gameplan. Or if they did, they didn't stick to it. City's talented players were able to exploit United's weaknesses. Everything about the match was disappointing to me.
"United are inconsistent. I see no evidence of a plan when I watch them. On paper, they have a talented squad but it doesn't work out for them on the pitch.
"The players and the manager must ask themselves: 'What more can I do? How can I do more for this team?' They need to take responsibility."
One of the players who has come under the most fire is Maguire, having already been the subject of scrutiny during an inconsistent season.
While Berbatov is confident that the England defender can turn his Old Trafford career around, he has advised Rangnick to take Maguire out of the side for now.
"I played with some great leaders at United, such as Nemanja Vidic and Wayne Rooney, and when things are not going well for the team the finger is always pointed at the captain," he continued.
"Harry Maguire can perform better. He knows that.
"The mistakes he is making are damaging his ability to lead the team. He needs to correct his positioning and work on his decision-making.
"It's not easy, when you are under pressure, but I have been there and that is the nature of playing for a top club. It is part of being a professional. You need to deal with it.
"Ralf Rangnick can step in here. Maybe he needs to give Maguire a rest and give somebody else a chance."
Maguire was recently dropped to the bench for the dismal 1-1 draw with Watford. United face Antonio Conte's Tottenham, fresh from their 5-0 thumping of Everton on Monday night, at Old Trafford on Saturday.
