Lewis Hamilton has tipped championship leader Jenson Button to succeed him as world champion following the Brawn's driver dream start to the season.
Button has won four of the first five races and is leading team-mate Rubens Barrichello by 14 points ahead of next weekend's Monaco Grand Prix, the sixth round of the championship.
Hamilton is 32 points behind and his McLaren team has been unable to fight near the front so far this year.
"I think Jenson's got a great chance, a great shot at it so I wish him all the best," Hamilton told Reuters in an interview.
"I think if I were to wish anyone (else) to win, it would be him."
He added: "I think it's a great story, so I wish him all the luck. They (Brawn) are going to have a great car there (in Monaco) so to beat them will be very tough. I don't think he has ever won there ... it will be a very special one for him to add to his list."
The McLaren driver says he will push as hard as possible to retain his crown, but he is aware that things would have to change very quickly for him to have a realistic chance.
"I want to win the world championship, we are a long way behind in points. I've never been as far behind or ahead in points before," he added.
"There's a lot of races left and if the car in front that is leading doesn't finish the next 10 races ... it's never over until it's over. For sure when we get to mid-season if we've still not scored many points, then we will have to knock it on the head.
"We'll keep pushing to try and win races in the year but clearly defending the world championship is (will be) out of the question."
Hamilton reckons the upcoming race in Monaco, where aerodynamics are not so important, is likely to be hist best shot at winning a race this year.
"Monaco will be one of the circuits, at least up until now, where we have the best chances of winning," he said. "It doesn't mean we will, but we arrive hopefully with a better package and able to turn things around.
"This is my favourite circuit, and especially after having won there it will be great to go there again and have another shot at it. But it will be tough for us this year."