United are sixth in the Premiership, already 11 points behind reigning champions Arsenal, after winning just three of their opening nine matches.

And Ferguson believes that he must shoulder the blame after making too many changes to his lineup this season.

"I definitely believe we have got the right players," said Ferguson. "At the minute I'm picking the wrong teams for a variety of reasons.

"Maybe I have been making too many changes.

"We have not had a consistency in selection and that has affected our performance."

United's latest setback was a scoreless draw at Birmingham.

"At Birmingham on Saturday I thought Ronaldo would be fresh enough after being away with Portugal. But he was not. The first thing he did when he got on the bus after the game was fall asleep. I made a mistake there.

"And we accept the mistake of the pre-season campaign was calling players back too early.

"Paul Scholes was one. As can - and did - happen he got an injury."

United will look for a confidence boost ahead of Sunday's showdown with Arsenal at Old Trafford with a win in their Champions League against Sparta Prague on Tuesday evening.

Three points against the Czechs on the back of the 6-2 win over Fenerbache and 2-2 draw with Lyon, will edge United ever closer to the crucial 10 point-mark which should secure qualification for the next stages.