Luiz Felipe Scolari lamented the injury-time goal at the end of the first half against Manchester United on Sunday, which forced him to change his tactics.

We had looked comfortable at 0-0 against the champions before Nemanja Vidic's far post header in stoppage time gave United the lead.

Further goals arrived from Wayne Rooney and Dimitar Berbatov to round off a disappointing day in the north as we lucklessly chased the game.

'We conceded a goal that changed the game because after this goal they played more free. We tried to put more players in front and gave them the space they wanted to play,' he explained. 'They are better than us in that time and scored one more goal by foul. It is one more mistake and in that time sure, 45 minutes they played very well, better than us.'

It leaves United right just a point behind us in the table, with two games in hand to play in the coming weeks. Asked whether Sir Alex Ferguson's side should now be counted as favourites for the championship, Scolari responded after some consideration.

'I don't know if I win or not win, we have 16, 17 games, and who knows what happens. If we play as today, as [the last] three or four games, sure, we will not win,' he conceded.

'But now is the time for me and the players, to be thinking about the future. We lose everything, or we are men and we regroup. This is the time, it is only this way. The second way is dead.

'I am not a man for this and my players I think are not the men for this. They try after today thinking about what has happened the last four or five games, thinking about the future, about us, and the next game maybe we play better than the last four or five and we start again to win, and arrive in a very good position.

'We don't know if the other teams will not lose, in England you never know. If you play first against 18th or 19th, you don't know. But sure, we know, the fans know and the press know, if we play as the second [half], we will not arrive, sure.'

Scolari refused to attribute the defeat to a lack of fitness or freshness, pointing out that the players and staff had had a full week to prepare.

'Never tired,' he said. 'They played the last game seven, eight days ago. They are in good condition… It is my responsibility; I need to change the system or something more. They try to do the best, maybe mistakes, maybe wrong, but it is my job now to change something.

'They have spirit, they try, but again one mistake in the last minute and we conceded. The second [half], if I want to lose 1-0 I keep my team with one more in midfield but I needed to change.'

He also ruled out the possibility of adding to his squad, adding that he believes he has the talent already at the club to succeed, using youngster Franco Di Santo as an example, and first explaining the decision to leave Nicolas Anelka on the bench for the start.

'I think Didier [Drogba] is in good condition and I believe in Didier as a number nine. I put him in for one game, two games.

'I know that more players do not arrive, I don't want more players. I have very good players, and this is my squad, finished.

'I try to give more opportunities [to Di Santo], he came to the pitch and played well, today I put him on because he is one player I need to give opportunities.'

Highlights of the game are available from midnight on both Chelsea TV and Chelsea Plus.