Manchester United boss Sir Alex Ferguson acknowledged his team were not good enough as they 2-0 lost at Fulham.
The defeat, on the back of last week's 4-1 home reverse against Liverpool, means the Barclays Premier League leaders have suffered back-to-back league defeats for the first time in 147 games.
After Danny Murphy (penalty) and Zoltan Gera had scored in each half to condemn his team to a 2-0 defeat, Ferguson said: "In the first half we never got started. They were lively and got stuck in and we respect that - they lost 4-0 to us a couple of weeks ago. But it's disappointing we didn't meet the challenge."
He added: "If you lose games in March and April it can cost you. Fortunately we have a slender lead at the moment but not a lot and I'm hoping we come back from the internationals back to our best."
Paul Scholes and Wayne Rooney were both sent off by referee Phil Dowd - Scholes in the 17th minute for handling a Bobby Zamora header on the goal line and substitute Rooney for a second bookable offence.
The latter dismissal frustrated Ferguson, who added on MUTV: "Did he (Rooney) throw the ball at the referee? The ball was thrown direct to where the free-kick was being taken - did it hit the referee? No.
"He threw it because he wanted to get the game going. What can you say about that?
"There wasn't a bad tackle in the game but John Pantsil was booked in the first half for nothing - it was just a tackle. Tackling isn't always perfect - I thought it was totally unfair.
"But there's no point talking about the referee - we didn't play well enough to win the game in the first half and that's why we lost it.
"In the second half I thought we did really well - they kept going and credit to them. But we're home to Aston Villa in our next game - and that will be crucial."
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