Michael Schumacher has finally acknowledged that his comeback season in 2010 was a bitter disappointment ­ and that the whole experience caught him slightly off-guard when it failed so dramatically to live up to expectations.

Up to now the seven times world champion has put a philosophical spin on his time in the 19 race series, trying to radiate an optimistic gloss on the experience.

But now he has come clean and cofessed just what a bruising and unexpected experience it has all been. The underlying problem was that all the effort expended on pushing so hard to help Jenson Button to see off the Red Bull challenge for the 2009 world championship left the nascent Mercedes squad in a position where they had to rush through the development of their car for the current season and lost a few tricks as a result.

"There is really only one goal, and that's winning," Schumacher confessed to the Swiss  magazine 'Blick'. "The team won the world championship last year, so it's pretty hard for everyone to have a season like we had."