Mercedes GP team principal Ross Brawn is expecting the 2010 championship battle to be "super hard" following the end of preseason testing.
Brawn's team took both titles last year after having started the season with a significant performance advantage over rival squads. But, after preseason testing came to an end on Sunday, Brawn believes his team will not be able to enjoy the same kind of advantage as in 2009, and reckons the fight for the title will be extremely close.
"The feeling last year was primarily relief that we got there, and then the added bonus of the performance of the car," said Brawn, whose team was saved by an eleventh-hour deal last year. "There's probably only two or three times in my career where I've started the season with such a performance advantage.
"I think most people would say the same, it's very rare for someone to start the season with such an advantage. But this is special in a different way. Obviously representing Mercedes GP now, bringing back the Silver Arrows to racing, but all the teams are quite close so I think it's going to be a super hard battle this year. Last year, we had a big advantage and then it was a case of hanging onto it for as long as we could."
The Briton admits he is not thinking about the title defense, but rather about focusing on doing the best job possible.
"I think you always feel like you are starting again," he said. "The races and championships you win disappear very quickly. They last a few weeks after the season finishes, and then you become totally embroiled in the new car and the new championship. So, I don't think it has entered my thoughts that we are defending the championship; it's more about how we can do the best job this year."