Button made his F1 debut in 2000 and joined Honda in 2003
Jenson Button's Formula One career may be over unless current team Honda find a new owner, former driver David Coulthard has warned.
With every other team having confirmed their line-up, Button's only chance of a drive in 2009 looks to be with Honda, who were put up for sale in December.
"You cannot say 100%, but it would be very difficult to imagine where he goes from there.
"It is a fickle business," said Coulthard, who retired last year.
Coulthard believes his 29-year-old fellow Briton cannot afford to sit out a season if Honda do not make the grid.
"The way the sport is now, there are so many young drivers coming through and there are so many opportunities for teams to pick up these guys," he added.
Honda announced they were pulling out of Formula One in December, blaming the global economic crisis.
The team remain hopeful of a rescue bid, but with the season beginning in Melbourne on 29 March, time is running out.
Coulthard, speaking at the launch of Red Bull's new car in Spain, warned that even if the team are bought out, Button could still experience a hugely frustrating season at the back of the grid.
"Honda, off the back of a bad season, suddenly when they realise they are up for sale start talking that this (their 2009 car) is a winning design and it's a great opportunity for anyone to buy this winning design," Coulthard said.
"I don't think it is a given that it will suddenly be a winning design.
"You would like to imagine that it would be better than what they were given last year but I think the team at the back of the grid potentially could be Honda.
"Whereas going into previous years with Honda he was all full of hope and expectation that this could be the year that Honda will step up, he has to take a different view now.
"He has to now consider himself as driving for a mid-grid, privateer team.
"Whether they can deliver to his expectations or not is more difficult to judge going into this season and presumably longer term he has to be looking to try to make a step up to a manufacturer team."