Jenson Button all but wrote off Honda's chances of making a winning start to the 2007 season in Sunday's Australian Grand Prix.

The 27-year-old Briton enjoyed something of a breakthrough year in 2006, claiming his first race win at the 113th attempt and finishing the season in a flurry by outscoring all other drivers during the last six races of the campaign.

But Honda had failed to press on in the close season, Button told reporters on Thursday, and he and team mate Rubens Barrichello were left with an uphill task to compete with the likes of Ferrari, Renault and McLaren at Albert Park.

"It's not a nice way to start a season. Arriving with a car that isn't challenging for victory hurts," said Button, who said his chances of emulating last season's pole position in Melbourne were slim.

"Here I can't see us qualifying in the top 10. I think if we have a good race -- because we are very reliable and some of the teams aren't -- I can see us finishing in the top 10. We're not going to get on the podium, we're not going to win the race."

Honda, who finished fourth in the title race last year, have been struggling during testing, while Button missed some of the close season after cracking his ribs during a karting accident.

He was disappointed the team had been unable to capitalise on the barnstorming finish to 2006.

"You're always hoping you're going to have a car that's capable of winning races. After last year's performance towards the end of the year, we didn't have the best car but we were in the top three teams, I'd say."

Button said the weekend would be used as extended test session for his struggling team.

"It's an important race but it's not about the end result," Button said.

"We've got to look at the areas where we're lacking and the areas where we need to work on compared to the top teams. It's more of a big test session for us, to learn why we're so far off."

Button said improvements in aerodynamics, which may be seen in the car by the second race of the season in Malaysia next month, would bring his team back to the field.