Luiz Felipe Scolari has admitted Chelsea will be out of the Premier League title race if they have many more days like the one they experienced at Old Trafford this afternoon.
The Blues suffered their worst loss at the Theatre of Dreams for 15 years as Manchester United ran riot in the second half, after Nemanja Vidic had opened the scoring just before the break.
It means Chelsea are now just a point ahead of United, who have two games in hand, and four adrift of current pace setters Liverpool.
And while Scolari is not throwing in the towel just yet, he accepts his side will have to improve.
"We have another 17 games left so who knows what will happen?'' said Scolari.
"But if we play three or four games like today, we will not win it.
"Now is the time to think about the future. We need to be men and improve. We cannot afford to think we have lost everything.
"I am not someone who thinks like this and I don't think my players are either.''
Yet Scolari could not have been impressed at the way his side capitulated after half-time.
Wayne Rooney and Dimitar Berbatov increased United's winning margin to 3-0. But it could have been more and Edwin van der Sar did not have a save to make at the other end.
Little wonder some Blues fans are questioning Roman Abramovich's refusal to bring in new players during the transfer window.
Not that Scolari feels he needs them.
"I don't think new players will arrive and I don't want them anyway,'' he said.
"This is my squad and we will fight until the last game. I do not think it is over just because we lost one match.''
However, if Scolari's team should lose their FA Cup replay at Southend on Wednesday, major questions will be asked of the Brazilian.
Scolari's efforts were not helped by the presence of Jose Mourinho in the directors' box ahead of Inter Milan's Champions League meeting with United next month.
Unfavourable comparisons are bound to be made between the pair, although Scolari insists he feels no extra pressure.
"Mourinho came here to watch Manchester United, that is normal,'' said Scolari.
"Mourinho is an intelligent man. He didn't come here to tell me he loves me.''
United had been smarting at Cristiano Ronaldo having a header ruled out by referee Howard Webb following a training ground corner routine.
Wayne Rooney ambled over and rolled them ball into and then out of the D, which should have made it in play when Ryan Giggs collected possession and crossed for the man set to be crowned FIFA world player of the year in Zurich tomorrow.
"I think the linesman got it wrong,'' said Rooney.
"We have practised in training and I don't see the problem.''
Thankfully for United, Vidic scored from the re-take, paving the way for a comfortable win which could launch the Red Devils back to the top by Saturday night if they beat Wigan on Wednesday and Bolton at the weekend.
"It is down to us now,'' said Rooney.
"If we win those two games we will be top of the league on Saturday night before Liverpool play Everton on Monday.''
United have yet to lose on home soil this season, winning eight on the trot since an opening-day draw against Newcastle.
And Ferguson feels if his side keep that run going, they will have a fantastic chance of retaining their title.
"It is a significant result for us,'' he said.
"We are chasing Liverpool and we are a bit nearer now. If our home form remains good we will have a great chance.''
Meanwhile, Scolari refused to discuss the disgraceful chants of Chelsea fans about the car crash involving Ronaldo on Thursday.
"When I hear about the crash and saw the car afterwards I said to Cristiano he should thank God every day, we want him to live until he is 90,'' the former Portugal coach reflected.
"I don't know what the fans sang because my focus was on the game.''