After his stunning loss to Tomas Berdych in the pre quarterfinals of Miami Masters, World No 1 Roger Federer admitted that his performance has taken dip after winning the Australian Open this year and he need to re-work on his game.

"Look, it's no secret I've struggled the last, what is it, five matches I've played here in the States.  It's disappointing, I think, my performance overall, if I've got to analyze right now after the match. But I fought as much as I could under the understood circumstances with my game having issues at the moment."

He added "I definitely lack timing.  I don't know where that comes from because I played so nicely in Australia.  So it's disappointing to not be able to back it up."

Federer said that the lung infection which kept him off court in February could have been a contributing factor. "Maybe the sickness did take it out of me more than I thought. Maybe the break was quite long. I'm kind of used to those things, I could have done much better."

Prior to this Federer suffered a early exit in Indian Wells also, by the hands of Marcus Baghdatis of Cyprus. 

"I was a couple points away this week and then also in Indian Wells I had my chances. It's disappointing having had a chance to move on. Maybe I had a chance to sort of turn around my game."

"But we'll see how it goes forward. The lack of confidence cost me these last two tournaments."

"But it only fuels my desire to go back to the practise courts and come back even stronger. I don't like to lose these type of the matches."

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